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File sharing is the practice of making files available for other users to download over the Internet and smaller networks. Usually file sharing follows the peer-to-peer (P2P) model, where the files are stored on and served by personal computers of the users. Most people who engage in file sharing are also downloading files that other users share. Sometimes these two activities are linked together. P2P file sharing is distinct from file trading in that downloading files from a P2P network does not require uploading, although some networks either provide incentives for uploading such as credits or force the sharing of files being currently downloaded.

 

The first P2P-generation: Server-client

The first generation of peer-to-peer file sharing networks had a centralized file list. Ultimately, Napster was held liable even if it used the most advanced technology available to identify works copyright holders had asked it to block, because no technology that can identify works with 100% certainty exists. Napster still exists today, but as a subsidiary of Roxio after they bought the name during the original Napster's bankruptcy phase, continues to operate today, and is now legally distributing music under a subscription-based model.

In the centralized peer-to-peer model, a user would send a search to the centralized server of what they were looking for, that is, a song, video, or movie. The server then sends back a list of which peers have the data and facilitates the connection and download.

The first file sharing programs marked themselves by inquiries to a server, either the data to the Download held ready or in appropriate different Peers and so-called Nodes further-obtained, so that one could download there. Best example was Napster (today a Payment offerer) or eDonkey2000 in the server version (today likewise with Overnet and KAD - network decentralized).

 

+ نوشته شده در  پنجشنبه چهارم مرداد 1386ساعت 23:49  توسط beta  | 
.
DRAM types

In electronic engineering, DDR2 SDRAM or double-data-rate two synchronous dynamic random access memory is a random access memory technology used for high speed storage of the working data of a computer or other digital electronic device.

It is a part of the SDRAM (synchronous dynamic random access memory) family of technologies, which is one of many DRAM (dynamic random access memory) implementations, and is an evolutionary improvement over its predecessor, DDR SDRAM.

Its primary benefit is the ability to run its bus at twice the speed of the memory cells it contains, thus enabling faster bus speeds and higher peak throughputs than earlier technologies. This is achieved at the cost of higher latency.

A 1 GiB DDR2 SDRAM with heatspreader
A 1 GiB DDR2 SDRAM with heatspreader
A 512 MiB DDR2 533 module with BGA chips.
A 512 MiB DDR2 533 module with BGA chips.

Like all SDRAM implementations, DDR2 stores memory in memory cells that are activated with the use of a clock signal to synchronize their operation with an external data bus. Like DDR before it, DDR2 cells transfer data both on the rising and falling edge of the clock (a technique called double pumping). The key difference between DDR and DDR2 is that in DDR2 the bus is clocked at twice the speed of the memory cells, so four words of data can be transferred per memory cell cycle. Thus, without speeding up the memory cells themselves, DDR2 can effectively operate at twice the bus speed of DDR.

DDR2's bus frequency is boosted by electrical interface improvements, on-die termination, prefetch buffers and off-chip drivers. However, latency is greatly increased as a trade-off. The DDR2 prefetch buffer is 4 bits deep, whereas it is 2 bits deep for DDR and 8 bits deep for DDR3. While DDR SDRAM has typical read latencies of between 2 and 3 bus cycles, DDR2 may have read latencies between 3 and 9 cycles. Because of this higher latency, DDR SDRAM running at the same bus speed as DDR2 is generally considered superior; DDR2 is, however, able to run at substantially higher bus speeds which equates to an overall increase in throughput.

Another cost of the increased speed is the requirement that the chips are packaged in a more expensive and more difficult to assemble BGA package as compared to the TSSOP package of the previous memory generations such as DDR and SDRAM. This packaging change was necessary to maintain signal integrity at higher speeds.[citation needed]

Power savings are achieved primarily due to an improved manufacturing process through die shrinkage, resulting in a drop in operating voltage (1.8 V compared to DDR's 2.5 V). The lower memory clock frequency may also enable power reductions in applications that do not require the highest available speed.

 

Standard name Memory clock I/O Bus clock Data transfers per second
DDR2-400 100 MHz 200 MHz 400 Million
DDR2-533 133 MHz 266 MHz 533 Million
DDR2-667 166 MHz 333 MHz 667 Million
DDR2-800 200 MHz 400 MHz 800 Million
DDR2-1066 (planned) 266 MHz 533 MHz 1066 Million

 

For use in PCs, DDR2 SDRAM is supplied in DIMMs with 240 pins and a single locating notch. DIMMs are identified by their peak transfer capacity (often called bandwidth).

Module name Bus clock Chip type Peak transfer rate
PC2-3200 200 MHz DDR2-400 3.200 GB/s
PC2-4200 266 MHz DDR2-533 4.264 GB/s
PC2-5300 333 MHz DDR2-667 5.336 GB/s1
PC2-6400 400 MHz DDR2-800 6.400 GB/s
PC2-8500 (planned) 533 MHz DDR2-1066 8.500 GB/s

Note: DDR2-xxx (or DDR-xxx) denotes effective clockspeed, whereas PC2-xxxx (or PC-xxxx) denotes theoretical bandwidth (though it is often rounded up or down). Bandwidth is calculated by taking transfers per second and multiplying by eight. This is because DDR2 memory modules transfer data on a bus that is 64 data bits wide, and since a byte comprises 8 bits, this equates to 8 bytes of data per transfer.

1 Some manufacturers label their DDR2-667 sticks as PC2-5400 instead of PC2-5300. At least one manufacturer has reported this reflects successful testing at a faster-than standard speed.[1]

In addition to bandwidth and capacity variants, modules can

  1. Optionally implement ECC, which is an extra data byte lane used for correcting minor errors and detecting major errors for better reliability. Modules with ECC are identified by an additional ECC in their designation. PC2-4200 ECC is a PC2-4200 module with ECC.
  2. Be "registered", which improves signal integrity (and hence potentially clock speed and physical slot capacity) by electrically buffering the signals at a cost of an extra clock of increased latency. Those modules are identified by an additional R in their designation, whereas non-registered (a.k.a. "unbuffered") RAM may be identified by an additional U in the designation. PC2-4200R is a registered PC2-4200 module, PC2-4200R ECC is the same module but with additional ECC.

Note: registered and unbuffered SDRAM generally cannot be mixed on the same channel.

 

DDR2 was introduced in the second quarter of 2003 at two initial speeds: 200 MHz (referred to as PC2-3200) and 266 MHz (PC2-4200). Both performed worse than the original DDR specification due to higher latency, which made total access times longer. However, the original DDR technology tops out at speeds around 266 MHz (533 MHz effective). Faster DDR chips exist, but JEDEC has stated that they will not be standardized. These modules are mostly manufacturer optimizations of highest-yielding chips, drawing significantly more power than slower-clocked modules, and usually do not offer much, if any, greater real-world performance.

DDR2 started to become competitive with the older DDR standard by the end of 2004, as modules with lower latencies became available.[2]

[edit] Backwards compatibility

DDR2 DIMMs are not backwards compatible with DDR DIMMs. The notch on DDR2 DIMMs is in a different position than DDR DIMMs, and the pin density is slightly higher than DDR DIMMs. DDR2 is a 240-pin module, DDR is a 184-pin module.

Faster DDR2 DIMMs though are compatible with slower DDR2 DIMMs. The memory would just run at the slower speed. Using slower DDR2 memory in a system capable of higher speeds results in the bus running at the speed of the slowest memory in use.

[Relation to GDDR memory

The first commercial product to claim using the "DDR2" technology was the NVIDIA GeForce FX 5800 graphics card. However, it is important to note that this GDDR-2 memory used on graphics cards is not DDR2 per se, but rather an early midpoint between DDR and DDR2 technologies. Using "DDR2" to refer to GDDR-2 is a colloquial misnomer. In particular, the performance-enhancing doubling of the I/O clock rate is missing. It had severe overheating issues due to the nominal DDR voltages. ATI has since designed the GDDR technology further, into GDDR3, which is more true to the DDR2 specifications, though with several additions suited for graphics cards.

GDDR3 is now commonly used in modern video cards. However, further confusion has been added to the mix with the appearance of budget and mid-range graphics cards which claim to use "DDR2". These cards actually use standard DDR2 chips designed for use as main system memory. These chips cannot achieve the clock speeds that GDDR3 can but are inexpensive enough to be used as memory on mid-range cards.

[edit] See also

[References

  1. ^ Mushkin PC2-5300 vs. Corsair PC2-5400
  2. ^ DDR2 vs. DDR: Revenge Gained

 

+ نوشته شده در  دوشنبه یکم مرداد 1386ساعت 11:43  توسط beta  | 
 

This little guide is to let people know some of the differances in computer DDR memory.

There are many differant type and makers of computer memory modules. Many of the manufactures of these memory modules use the same chips that are found on their compatitions modules, therefore name brand modules are not of much more quality than that of lesser known compaines, which means you can have a name brand and a generic brand in the same computer without any problems.

Even if a memory chip is compatible with your system doesn't mean it will always work. If you get one that doesn't work in you system, it may still work in another.

If you are looking for DDR memory (Double Data Rate) here are some things to remember.

1. Make sure that you are getting it with the right pin count.

2. DDR and DDR2 are not interchangeable. (for a desktop pc: DDR has 184 pins and DDR2 has 240 pins)

3. DDR-400 for example will only have a frequency of 200 not 400 if your system is not set up properly, most systems require you to have 2 modules in before your system will operate at DDR. Your system will not operate DDR with 1 or 3 modules in it. Because of this limitation it is better if you have 2 or 4 DDR modules in your system instead of one. For example 2 256MB modules will run faster than 1 512MB module

4. A 256MB PC-3200 DDR-400 184-pin Module for a PC is the same as the one for an iMac.

5. The Intel 875P, 865G, and 865PE chipsets have and architecture limitation as follows:

     *  Processors with a FSB-800 will support DDR-400

     *  Processors with a FSB-533 will support DDR-333 and DDR-266

     *  Processors with a FSB-400 will support DDR-266

     If your computer has one of these chipsets and you put DDR-400 memory modules in it, it is only going to run at DDR-266, therefore if your CPU only has a FSB of 400 (FSB-400) it should save you money if you use DDR-266 modules.

+ نوشته شده در  دوشنبه یکم مرداد 1386ساعت 11:36  توسط beta  | 

isoHunt is a major BitTorrent index with over 806,961 torrents in its database and over 12.11 million peers from indexed torrent.[1] With 7.4 million unique visitors as of May 2006, isoHunt is one of the most popular BitTorrent search engines. Thousands of torrents are added to it each day as well as deleted for a multitude of reasons. On average, isoHunt users perform over 40 million unique searches per month.

The website's founder Gary Fung is currently being sued for copyright infringement. On January 16, 2007, isoHunt was taken offline; stating that "Lawyers from our primary ISP decided to pull our plug without any advance notice". After a major hardware upgrade [2], the site resumed normal operation by January 22, although experiencing several subsequent brief periods of downtime due to server changes. On July 10, 2007 isoHunt was offline temporarily for unknown reasons.

+ نوشته شده در  پنجشنبه بیست و هشتم تیر 1386ساعت 2:15  توسط beta  | 
Windows XP is a line of proprietary operating systems developed by Microsoft for use on general-purpose computer systems, including home and business desktops, notebook computers, and media centers. The letters "XP" stand for experience.[2] Codenamed "Whistler" after Whistler, British Columbia, as many Microsoft employees skied at the Whistler-Blackcomb ski resort during its development, Windows XP is the successor to both Windows 2000 and Windows Me, and is the first consumer-oriented operating system produced by Microsoft to be built on the Windows NT kernel and architecture. Windows XP was first released on October 25, 2001, and over 400 million copies are in use, according to a January 2006 estimate by an IDC analyst.[3] It is succeeded by Windows Vista, which was released to volume license customers on November 8, 2006, and worldwide to the general public on January 30, 2007.

The most common editions of the operating system are Windows XP Home Edition, which is targeted at home users, and Windows XP Professional, which has additional features such as support for Windows Server domains and dual processors, and is targeted at power users and business clients. Windows XP Media Center Edition has additional multimedia features enhancing the ability to record and watch TV shows, watch DVDs, and listen to music. Windows XP Tablet PC Edition is designed to run the ink-aware Tablet PC platform. Two separate 64-bit versions of Windows XP were also released, Windows XP 64-bit Edition for IA-64 (Itanium) processors and Windows XP Professional x64 Edition for x86-64 processors.

Windows XP is known for its improved stability and efficiency over previous versions of Microsoft Windows. It presents a significantly redesigned graphical user interface, a change Microsoft promoted as more user-friendly than previous versions of Windows. New software management capabilities were introduced to avoid the "DLL hell" that plagued older consumer versions of Windows. It is also the first version of Windows to use product activation to combat software piracy, a restriction that did not sit well with some users and privacy advocates. Windows XP has also been criticized by some users for security vulnerabilities, tight integration of applications such as Internet Explorer and Windows Media Player, and for aspects of its user interface
+ نوشته شده در  یکشنبه بیست و چهارم تیر 1386ساعت 15:53  توسط beta  | 

Here at BlueNova Computing we see the results of PC users' most common mistakes. Well, now, you can benefit from their misfortune by reading about these common problems and also easy ways to avoid them yourself. Feel free to contact us if you have any questions or suggestions.

1. Misbehaved Programs - You've probably heard of spyware, also known as adware or malware. These programs are generally designed to run silently in the background and make money for some person or company somehow. Some spyware simply tracks your surfing habits in order to sell for marketing purposes, while others pop-up ads, redirect you to different sites, install toolbars, change settings, and worse. Spyware often requires expert help to remove, and can often

But where do these misbehaved programs come from? Spyware does not directly spread in the manner of a computer virus or worm. Spyware gets on your system either through security 'holes' in unsafe programs (see #2) or by hitching a ride with another program (like the ancient Trojan horse).

So do some research before you download, and use some common sense. If the program is designed to do something illegal or semi-legal (like P2P programs Kazaa, Limewire, Morpheus, etc.) don't be surprised if they take some liberties with your PC along the way. Especially beware of free utilities and screensavers, which are also a major source of spyware. However, some of our favorite programs are free; so the point is, make sure to check the source and exercise caution when downloading.

2. Unsafe Web Browser - Internet Explorer is the default browser on almost all new PCs. Don't use it! Internet Explorer is the most common point of entry for spyware. Even on a fully updated install of Windows, many websites can install spyware AUTOMATICALLY.

The solution is simple: just download and use a different web browser. We like Mozilla Firefox (free download), and Opera is also good (and free). You can visit all the same websites with Mozilla Firefox without having to worry about spyware. However, please note Firefox won't remove spyware or in any way actively protect your PC; it is simply a safe way of viewing websites.

3. Backup Your Data - We deal with damaged PCs, hard drives, and data loss on a regular basis, and we notice that very few PC users, even business owners, make regular backups of their data. So what's the best way backup your data?

Well, there are many options. First, don't rely on floppy disks; they are too delicate, slow, and only hold 1.4MB of data. CDRs are a popular choice, since they are inexpensive (about $0.25 each in bulk), most PCs have CD-writers, and you can backup 700MB at a time. Blank DVDs hold about 4500MB each. Some also use flash drives (usually 1024MB and up), or external USB hard drives (80,000MB and up). Small business owners may want to consider a more automated backup system, like using an extra hard drive along with reliable backup software (we use Acronis True Image).

4. Security Software - Most computer users know that they need some sort of antivirus protection. But if you visit the software store, you'll encounter a vast array of 'internet security products' designed to protect you from spyware, hackers, pop-ups, junk mail, and so forth. Should you go for the extra protection?

No. Really, just don't. The best way to avoid problems with your PC is to keep things simple. Most security software is a bloated mess of programs that accomplish little more than slowing down your PC. We regularly 'fix' computers by removing such software, which can conflict with other programs or cause other networking problems. Plus, the extra protection isn't necessary. If you follow steps #1, 4, 6 and 10, you won't have any problems from hackers, spyware, or pop-ups.

However, you should use some sort of anti-virus protection. Viruses can spread in unusual ways. So search out a simple anti-virus product (not Norton or McAfee) and make sure it stays up to date. See our eBay store for our recommendations.

5. Surge Suppressor - Most PCs that are damaged by surges and lightning, by far, are hit through the TELEPHONE line, not the power cord. Most modern surge suppressors include phone line protection. Use it. And be sure it's a good one, like an APC or Belkin brand; we've seen cheap ones that failed and let the computer get fried anyway.

6. Keeping Windows Updated - You need the latest security patches and service packs to avoid the latest exploits that hackers and viruses use to attack your PC. All window users should either turn on automatic updates or manually get them regularly.

Some users are paranoid about allowing Microsoft to send them updates, thinking that it might

7. Inkjet Printers - Inkjet printer ink is priced a little higher than gold right now. Seriously. So when you're shopping for a printer, check the ink cartridge prices too. Don't be tempted by that $39.99 Lexmark deal. If you price the cartridges, you'll see where they're making the money.

Also, if you are a small business owner and you print in large volumes, you NEED a monochrome laser printer. Remember to look past the higher price for the printer and the toner cartridge, and instead calculate the MUCH lower cost per-page and all the time you'll save. And if you think you'll miss color, see #8 below.

8. Printing Digital Photos - If you just read #7, you know that operating an inkjet printer can be expensive and time-consuming. It's doubly so with printing photos (photo paper, ink costs, cleaning print heads, etc.). So consider bringing your memory card or CD to a place like Walgreens, CVS or Target where you can use a simple kiosk to select and print photos quickly.

Even better, import all of your photos into Picasa (free download from Google) where you can crop and enhance them. Then select your favorite photos and click the [Order Prints] button to select from a variety of online printing services to send them to. If you don't mind waiting to receive them for a few days, getting prints this way is generally less expensive, easier, and many of these services offer several free prints for new customers.

9. E-mail Attachments - This is one of the biggest area of frustration for new PC users. The first mistake is usually trying to send a file that is too large.

What is too large? Well, consider the rate at which the other person will receive the file: On a dial-up connection, which most of your friends are probably still using, they'll be receiving the files at about 4 or 5kB per second. So if you send them a photo straight from your 3 megapixel camera for instance, at about 900kB it will take 3 to 4 minutes per photo to download. Ouch. So resize that photo first before you send it.

Also, it's important to remember not to send someone a file that they can't open. For instance if you use WordPerfect to create a document, but your friend uses Microsoft Word, they won't be able to view it. What can you do? Pick up PDF Creator (free) to create a document that anyone can view and print, or you could both switch to OpenOffice (also free) which supports many document types and can also export to PDF.

10. Protect Your PC From Other Humans - That's right. Your friends and family can be one of the biggest threats to the health of your PC.

We see it all the time: Joe pays to have his PC cleaned and is told how to keep spyware out. Later, Bob comes over to check his e-mail, and then browses some 'fun' sites using Internet Explorer. Bob then decides to do you a favor and install some of his favorite free software. If you've read #1 and #4, you can imagine the state that Joe's PC is in right now.

What practical steps can be taken, other than locking the computer away? Well, if you use Windows XP,  just let them use the 'Guest' account built into Windows. You see, the Guest account doesn't allow users to install programs or to change system settings. Note that you may need to visit the User Accounts section of the Control Panel in Windows to enable the Guest account.

Using the Guest account may not work out well for a family member, though. Working in a limited account environment can be frustrating in the long term, and also some utilities and games don't function correctly in a limited account. So instead of trying to install some kind of draconian security software, it may be best to just sit the family down and explain the dangers (and expenses) of unsafe computing to them.

- Adam at Blue Nova Computing

Guide ID: 10000000000101354Guide created: 12/13/05 (updated 07/08/07)
+ نوشته شده در  دوشنبه هجدهم تیر 1386ساعت 0:42  توسط beta  | 

  This is an attempt to direct people to more specific fdisk help/utilities. If you know of others

then feel free to msg me with your suggestions. Please note that none of the places are affiliated with fdisk.com.

 

I often get questions about the DOS program FDISK. I don't mind the questions and I know a fair amount about partitioning drives. Just be aware I had nothing to do with creating the hardware

 

or software involved with the process and you are on your own if your data goes *poof*. If you want certified help then call the company that made the hardware--hardware companies are usually very helpful.

If you were looking for some walkthroughs or someone looking for questions to answer, try 5starsupport.

Also available is Radified FDISK Guide to Partitioning a Hard Drive

Microsoft Help:

  • How to partition and format a hard disk in Windows XP
  • How to Use the Fdisk Tool and the Format Tool to Partition or Repartition a Hard Disk
  • Using debug to wipe partitions.

    Can I repartition my hard disk into one large partition without loosing my data? It isn't as simple as it might seem. Any applications not on the C: drive will have references directed at the old location. They

  •  

  • won't work very well once you move them. Its also more of a pain then it might seem to change the number of partitions on one drive. Basically, if you don't already know how to do it then you would be better off just backing up your data and starting over with a fresh install.

    This debug script (from Bill) and a win98 boot disk will wipe any drive of its pointers letting you start with a clear table. This should help if your drive is so messed up that fdisk complains that it can't deal with the drive information or crashes. Alternatively, if you'd rather not contend with assembly language commands and DEBUG, a simple program called 'Partition Zapper' is available at http://www.meixler-tech.com/pzapper/ which will clear the partition table in a few keystrokes (cost: $12).

    If your fdisk is having problems or you are in need of a copy, you can get the Free(DOS) Fdisk which is now ready for prime time and supports many features not even in the standard DOS version. This can also handle many partition jobs that regular fdisk fails on.

    Tom Kuurstra and Joep van Steen of DIY DataRecovery have created a number of tools to help people recover data, search or modify hard drives and edit or save MBR information. One tool can even modify saved MBR copies. They are also willing to help people personally as long as you treat them with respect and provide the information needed to help you.

    HDD provides disaster recovery solutions for an accidental format, accidental fdisk, file recovery. Before and after the event.

    Diskman is another up and coming disk recovery, backup and manipulation tool by James Clark. "Mount and manipulate disk images" sounds like a tasty option. ZhanFeng also makes something called diskman, but everything is in Chinese so I have no idea what its deal is.

    If you happen to get the CIH virus, here is a program that can potentially recover your data. I haven't tried it yet as I don't have a CIH infected computer. Also, remember that you should turn back the BIOS date on the infected computer to early 1998 before fixing it and scan/disinfect right after recovering because the virus may still be there! Good luck. Here is another free recovery tool at grc.com.

    There are some handy disk utilities at simtelnet especially in the bootutil and diskutil areas. You can also use their excellent search to find other tools.

    You could also look around http://www.bootdisk.com/ and they might have something to bail you out of a jam. PCHelpLIVE.com also has a booting soltion for people in need as well as other PC help stuff.

    If you are looking for a technical description on the subject of partitions, check out Partition Tables - Focus on OS/2 - 09/02/98. If you dig reading then PC Guide's enormous Hard Disk Drives reference section is sure to interest you.

    If you are looking for a tutorial on partitioning your drive, try Weendoggy's Homepage or Microsoft Support on How to Install Windows 98 on a Computer with No Operating System. Dan's Data has a good page on Upgrading your hard drive.

    Computer Hope has a very nice online simulation of fdisk available for people to fool around without chance of blowing anything up. They also have some more information about the command line switches and such.

    Wondering what the Volume Serial Number is all about? Check Brett Glass's site and he will clear it all up.

    Old hard drive specs can be found at TheRef and Blue Planet.

    People who badly need to recover their lost/deleted data should try Lost and Found by Powerquest. You have to buy it to get your data restored, but I have been told it is very successful and also easy for novices to use.

    If you want a supported product for resizing disk partitions then you should check out PartitionMagic or Partition Commander.

    If you are willing to live dangerously, there is a free program called FIPS that can do nondestructive splitting of harddisk partitions. It does not join partitions. I have used it once or twice in the past and it worked great, but I URGE everyone to read the directions before trying it!

    The Partition Resizer is one I haven't tried, but it looks promising.

    The Randish Partition Manager site hasfree software that can manipulate/save partitions as well as a boot manager. It also has a primer on partitioning and some other great information. I have not tried the Ranish Partition Manager yet myself.

    Here are some links that people sent me:

    Yaru pointed me to http://how.to/use_Partition_Doctor. It is both the download location and instructions on using Partition Doctor, a program for inspecting your partition table for errors and fixing the correctable ones. He also has some good partition site links.

    Andrew sent over a link on Dr Solomon's anti virus web site that says not to use FDISK /MBR to kill viruses. I don't agree that you should never use it, but it was a good read anyhow.

    Robert sent me the following link that contains a few more fdisk switches then I have: http://www.jacobsen.sdn.dk/fdisk/ Undocumented FDISK. He also has a good install info page for win95 and some good utilities off his main page.

    Alan found a great link at Maxtor that covers hard drive capacity barriers, so (for instance) if you don't understand why you only see 8.4 gig of your new 12 gig drive then check that out! 528 MB, 2.1 GB, 4.2 GB and 8.4 GB limitations are covered. One thing to note, however, I got a message from Kat that said when she installed a new drive with Maxblast's EZ-BIOS many applications didn't function properly. I have no idea if it was a bios problem or if apps really don't like the disk managers, but it is something to watch for. Anantya sent over a link to Seagate's info on hard drive capacity barriers. They also have a downloadable copy of their diskmanager if you have a Seagate drive that you can't get you computer to fully utilize.

    http://www.compguystechweb.com/ has some good information on drive problems and a separate fdisk help section too.

    Ghostsoft: They make a nice disk clone tool that uses a text interface or just the command line.

    HDCopy: Apparently a HD copy utility company, but I know nothing about them.

    Gibson Research Corporation: They make the SpinRite utility for repairing drives (Yes, it still exists!). If you have an IOMega Zip or Jaz drive, you might want to check out their Click Of Death Research Resource Page which has a test for the problem.

    MasterBooter makes a companion program to their boot manager called EFDISK. They say it can be completely driven from the command line! Untested by me.

    Someone sent me an FDISK.HLP.zip Windows help file for FDISK. I didn't even know that one was available!

    Walter mentioned an old dos utility called delpart that can be easily found via web search which can wipe ntfs and other sticky types of partitions. It can be found in the file systems section of the (very nice) SavillTech NTFAQ site which has all sorts of good NT stuff.

    If you are looking for information on NT file systems, check out the file system section of http://www.ntfaq.com/. Walter turned me on to them when he introduced me to the delpart program for getting rid of sticky partitions. It is still there, but now I recommend the infamous debug script instead.

    Somebody from Codework sent over a link for RapiDeploy, an imaging/cloning tool that can personalize each pc as it is cloned.

    Here is an interesting link to Circuitmasters HD tech page sent over by a third party (Roy). They have some interesting info about drives as well as other hardware too.

    Ken over at ACR Data Recovery Services says that a few of my visitors told him to ask for a link. He has software that is used for repairing boot sectors and partition tables for DOS, Win95/98 and WinNT/2000 (FAT16, FAT32, NTFS) formatted hard drives and removable media. Sounds like good stuff! Check it out at http://www.atl-datarecovery.com/bp.htm.

    If you want to pay someone to recover your data, http://www.averdrivetronics.com is one company that will do it.

    If you are looking for raw info about drives and stuff, PC Guide has some fantastic info up in their Hard Disk Drives section!

    I received a nice e-mail from a person named James that I thought I would pass on. It contains a bit of info that may help others:

    I had a problem which I have never seen before and I been a systems administrator for about 5 years. I had this 4.2GB Fujitsu drive that I was trying to clear off. It had a primary partition, and an extended partition with no logical disks specified. I tried to delete the extended partition but I kept getting an error saying that I couldn't delete the extended partition with logical drives existing. So I try to delete the logical drives, but there aren't any. So I was stuck on it for an hour. I got desperate and decided to surf the web. I would a site that had very little info but had just what I needed. The site specified that there are undocumented switches that work with FDISK. I already knew that there was an /MBR switch to repair the master boot record, because I has to use it many times. I found much more! I was able to force fdisk to create a logical partition from the command line, Then I was able to delete the logical, extended, then finally the primary partition. I though that you may find these useful and could possibly post them on your site for people like me that happened to surf in to find hard to find info. Here they are: 

    Undocumented or little known FDISK parameters:
FDISK 1/PRI:100 - Command line to create a 100 meg DOS partition on hard 
drive 1.
FDISK 1/EXT:500 - Command line to create a 500 meg extended DOS partition 
on hard drive 1.
FDISK 1/LOG:250 - Command line to create a 250 logical drives.

FDISK /STATUS - Shows you the current status of your hard drives.
FDISK /MBR  - Repair the master boot record.
FDISK /X - Ignores extended disk-access support. Use this switch if you
receive disk access or stack overflow messages.
    John McDonald clarified the /q switch:
    FDISK /Q - prevents fdisk from booting the system automatically after exiting fdisk.
    Kim Rickaby has seen this as a result of DOS/Win95 incompatibilities:

    What it turned out to be is that I was booting to a 6.22 floppy disk and running fdisk. Fdisk would see the primary and extended but would not let me delete the extended as it believed they was a logical partition which I could not see. However the problem was cause by the disk had been setup by Windows OSR2. When I booted of a floppy that had OSR2 and the Fdisk program for it I was then able to see the logical partition and therefor could delete it.
    Ted Fines had some additional information to share about this problem:

    If you have OS/2 on your system and you create a boot manager partition, you'll find that you can't get rid of it with DOS FDISK. This may be what happened to James.

    To get rid of the unwanted partition, one has to either reinstall OS/2, use an OS/2 boot disk with the OS/2 FDISK utility, or...

    If the BIOS has a format hard disk utility, it will wipe out the OS/2 partition. Otherwise, try to mess up the hard disk even worse than OS/2 has. Use Norton Disk Doctor to hose up the FAT and Partition table. Then, you'll be able to use DOS FDISK, since it will just see your drive as garbage (as an unformatted drive).

    I advise being careful with the BIOS format utility. Some of those are low level formatters and that is not recommended by at least some HD manufacturers any more. Better to screw up the drive with a disk doctor, or get a better fdisk than DOS's (some listed above).

    Ryan sent in a nice chunk about scripting fdisk.

    Bob pointed out that a Linux rescue/repair disk will have an fdisk capable of wiping almost any partition. I would bet that freebsd also has one too. I have omitted this info in the past due to the learning curve, but I guess people are ready now.

    There is even more interesting fdisk information at MS-DOS Hidden Secrets. It also has secret switches for other DOS commands.

    Marian Hubinsky sent over ata.exe which I have zipped up. It is a program which shows connected ata compatible devices. It supports 4 ata ports and shows detailed info about hard drives and other stuff.

    http://help-site.com/ has a lot of OS help.

    A quick tip from Kevin for people having trouble with KG7-RAID boards:

    I made a 98 boot disk; booted the machine to it with cd support; checked the I386 file on the cd-no probs there. I then ran winnt.exe; it told me the disk needed to be formatted; i ran fdisk the machine said there were no fixed disks. I then checked jumper on hd-it's set to master. Cable is correct plugged into ide1. Bios sees it.

    And his self-found solution:

    The WDC hard drive needs to be jumped 4&6 (neutral).

    That's all it for now.

    [www.fdisk.com]
    • + نوشته شده در  شنبه دوم تیر 1386ساعت 2:39  توسط beta  | 
     

     

    Hiren's Boot CD is a boot CD containing various diagnostic programs such as partitioning agents, system performance benchmarks, disk cloning and

    imaging tools, data recovery tools, MBR tools, BIOS tools, and many others for fixing various computer problems. It is a bootable CD; thus, it can be

    useful even if the primary operating system cannot be booted. Hiren's Boot CD has an extensive list of software. Utilities with similar functionality on the CD

    are grouped together and seem redundant; however, they present choices through UI differences. As of May 28th, 2007 the current version of the CD is

    9.1.

     

    See the Warez and Copyright infringement of software articles.

     

    Even though Hiren's Boot CD contains free software and abandonware, which are still copyrighted, from the DOS era, it should be noted that there are also

    a significant number of unlicensed proprietary software on Hiren's Boot CD; therefore, Hiren's Boot CD is considered warez. This makes the entire disc

    illegal in most jurisdictions. Hiren no longer offers a download link to the disc image.

     

     

    Retrieved from "http://en.wikipedia.org/wiki/Hiren%27s_boot_CD"
    + نوشته شده در  جمعه یکم تیر 1386ساعت 4:56  توسط beta  | 

     

     

     
    Windows XP loading drivers during a Safe Mode bootup
    Windows XP loading drivers during a Safe Mode bootup

    A device driver, or software driver is any computer program that allows other programs to interact with a computer hardware device, or else to work as if they are interacting with a particular device. In other words, a driver is an interface for communicating with the device, or emulates a device. A driver typically communicates with the device through the computer bus or communications subsystem that the hardware is connected to. When a program invokes a routine in the driver, the driver issues commands to the device, and when the device sends data, the driver invokes routines in the program.

    Drivers are hardware-dependent and operating-system specific. They usually provide the interrupt handling required for any necessary asynchronous time-dependent hardware interfacing needs.

     Rationale

    Computer hardware necessitates abstraction. Even the same types of devices differ. Manufacturers release newer models that provide more reliability or better performance. These newer models are often controlled differently and computers and their operating systems cannot be expected to know how to control every device, both now and in the future.

    To solve this problem, operating systems dictate how every type of device should be controlled. The device drivers purpose is to translate these OS mandated function calls into device specific commands. Theoretically, a new device, which is controlled in a new manner, should behave correctly if a suitable driver is available. This new driver will ensure that the device appears to operate as usual from the operating systems' point of view.

    Design

    Device drivers can be abstracted into logical and physical layers. Logical layers process data for a class of devices such as ethernet ports or disk drives. Physical layers communicate with a specific device instance. For example, a serial port needs to handle standard communication protocols such as XON/XOFF that are common for all serial port hardware. This would be managed by a serial port logical layer. However, the logical layer needs to communicate with a particular serial port chip. 16550 UART hardware differs from PL-011. The physical layer addressess these chip specific variations. Conventionally, OS requests go to the logical layer first. In turn, the logical layer calls upon the physical layer to implement OS requests in terms understandable by the hardware. Inversely, when a hardware device needs to respond to the OS, it uses the physical layer to speak through the logical layer.

    Depending on the specific computer architecture, drivers can be 8-bit, 16-bit, 32-bit, and more recently, 64-bit. This corresponds directly to the architecture of the operating system for which those drivers were developed. For example, in 16-bit Windows 3.11, most drivers were 16-bits, while most drivers for 32-bit Windows XP are 32-bit. More recently, specific 64-bit Windows versions have required hardware vendors to provide newer 64-bit drivers for their devices.

    Linux device drivers are built into the OS kernel, and thus get built for the appropriate bit-width automatically. Provided that sufficient technical information about the hardware is available, the Linux kernel team will write the drivers free of charge.[1][2][3] This absolves both hardware vendors and end users from having to worry about drivers.

    Additionally, the device drivers can either be built as parts of the kernel or can be built separately as loadable modules. The Windows(TM) .sys files and Linux .ko modules are loadable device drivers. The advantage of loadable device drivers is that they can be loaded only when necessary and then unloaded, thus saving kernel memory.

     Development

    Writing a device driver is usually difficult, as it requires an in-depth understanding of how the hardware and the software of a given platform function. Because many device drivers execute in kernel mode, software bugs often can damage the system. In contrast, most user-level software on modern operating systems can be stopped without greatly affecting the rest of the system. Even drivers executing in user mode can crash a system if the device is erroneously programmed. These factors make it more difficult and dangerous to diagnose problems.

    Thus drivers are usually written by software engineers who come from the companies that develop the hardware. This is because they have better information than most outsiders about the design of their hardware. Moreover, it was traditionally considered in the hardware manufacturer's interest to guarantee that their clients can use their hardware in an optimum way. Typically, the logical device driver (LDD) is written by the operating system vendor, while the physical device driver (PDD) is implemented by the device vendor. But in recent years non-vendors have written numerous device drivers, mainly for use with free operating systems. In such cases, it is important that the hardware manufacturer provides information how the device communicates. Although this information can instead be learned by reverse engineering, this is much more difficult with hardware than it is with software.

    Microsoft has attempted to reduce system instability due to poorly written device drivers, by creating a new framework for driver development, called Windows Driver Foundation (WDF). This includes User-Mode Driver Framework (UMDF) that encourages development of certain types of drivers - primarily those that implement a message-based protocol for communicating with their devices - as user mode drivers. If such drivers malfunction, they do not cause system instability. The Kernel-Mode Driver Framework (KMDF) model continues to allow development of kernel-mode device drivers, but attempts to provide standard implementations of functions that are well known to cause problems, including cancellation of I/O operations, power management, and plug and play device support.

    Apple has an open-source framework for developing drivers on Mac OS X called the I/O Kit.

     Device driver applications

    Because of the diversity of modern hardware and operating systems, many ways exist in which drivers can be used. Drivers are used for interfacing with:

    Common levels of abstraction for device drivers are

    • For hardware:
      • Interfacing directly
      • Using some higher-level interface (e.g. Video BIOS)
      • Using another lower-level device driver (e.g. file system drivers using disk drivers)
      • Simulating work with hardware, while doing something entirely different
    • For software:
      • Allowing the operating system direct access to hardware resources
      • Implementing only primitives
      • Implementing an interface for non-driver software (e.g. TWAIN)
      • Implementing a language, sometimes quite high-level (e.g. PostScript)

    Choosing and installing the correct device drivers for given hardware is often a key component of computer system configuration.

    Virtual device drivers

    A particular variant of device drivers are virtual device drivers. They are used in virtualization environments, for example when an MS-DOS program is run on a Microsoft Windows computer or when a guest operating system is run on, for example, a Xen host. Instead of enabling the guest operating system to dialog with hardware, virtual device drivers take the opposite role and emulate a piece of hardware, so that the guest operating system and its drivers running inside a virtual machine can have the illusion of accessing real hardware. Attempts by the guest operating system to access the hardware are routed to the virtual device driver in the host operating system as e.g. function calls. The virtual device driver can also send simulated processor-level events like interrupts into the virtual machine.

     Open drivers

    Driver APIs

     See also

    References

    1. ^ Greg Kroah-Hartman. Linux kernel monkey log - Free Linux Driver Development!. Retrieved on 2007-05-23.
    2. ^ Don Marti. Linux driver development project bears fruit. Retrieved on 2007-05-23.
    3. ^ Linux driver project wiki. Retrieved on 2007-06-14.

    External links

    Retrieved from "http://en.wikipedia.org/wiki/Device_driver"
    + نوشته شده در  پنجشنبه سی و یکم خرداد 1386ساعت 2:40  توسط beta  | 
    A programmable read-only memory (PROM) or field programmable read-only memory (FPROM) is a form of digital memory where the setting of each bit is locked by a fuse or antifuse. Such PROMs are used to store programs permanently. The key difference from a strict ROM is that the programming is applied after the device is constructed. They are frequently seen in video game consoles, or such products as electronic dictionaries, where PROMs for different languages can be substituted.

     Programming

    A typical PROM comes with all bits reading as 1. Burning a fuse during programming causes its bit to read as 0. The memory can be programmed just once after manufacturing by "blowing" the fuses (using a PROM blower), which is an irreversible process. Blowing a fuse opens a connection while blowing an antifuse closes a connection (hence the name). Programming is done by applying high-voltage pulses which are not encountered during normal operation (typically 12 to 21 volts). Read-only means that, unlike the case with conventional memory, the programming cannot be changed (at least not by the end user).

    Advantages

    • Reliability
    • Stores data permanently
    • Moderate price
    • Built using integrated circuits, rather than discrete components.
    • Fast: speed is between 35ns and 60ns.

     Invention

    PROM was invented in 1956 by Wen Tsing Chow, working for the Arma Division of the American Bosch Arma Corporation in Garden City, New York. The invention was conceived at the request of the United States Air Force to come up with a more flexible and secure way of storing the targeting constants in the Atlas E/F ICBM's airborne digital computer. The patent and associated technology was held under secrecy order for several years while the Atlas E/F was the main operational missile of the United States ICBM force. The term "burn," referring to the process of programming a PROM, is also in the original patent, as one of the original implementations was to literally burn the internal whiskers of diodes with a current overload to produce a circuit discontinuity. The first PROM programming machines were also developed by Arma engineers under Mr. Chow's direction and were located in Arma's Garden City lab and Air Force Strategic Air Command (SAC) headquarters.

     External link

    Retrieved from "http://en.wikipedia.org/wiki/Programmable_read-only_memory"
    + نوشته شده در  پنجشنبه سی و یکم خرداد 1386ساعت 2:30  توسط beta  | 
    BIOS: Basic Input/Output System

    Phoenix AwardBIOS CMOS (non-volatile memory) Setup utility on a standard PC
    Stored on:
    Common Manufacturers:

    BIOS (in computing, stands for Basic Input/Output Services also incorrectly known as Basic Integrated Operating System and occasionally Built In Operating System[citation needed]. BIOS refers to the firmware code run by an IBM compatible PC when first powered on. The primary function of the BIOS is to prepare the machine so other software programs stored on various media (such as hard drives, floppies, and CDs) can load, execute, and assume control of the PC[1]. This process is known as booting up.

    BIOS can also be said to be a coded program embedded on a chip that recognizes and controls various devices that make up the PC. The term BIOS is specific to personal computer vendors. Among other classes of computers, the generic terms boot monitor, boot loader or boot ROM are commonly used. Boot is short for bootstrapping.

    The term first appeared in the CP/M operating system, describing the part of CP/M loaded during boot time that interfaced directly with the hardware (CP/M machines usually had a simple boot loader in ROM, and nothing else). Most versions of DOS have a file called "IBMBIO.COM" or "IO.SYS" that is analogous to the CP/M disk BIOS.

     

     How the BIOS boots

    The BIOS runs off the PROM, EPROM or, most commonly, flash memory when the computer is powered on. It initializes several motherboard components and peripherals, including:

    • the clock generator,
    • the processors and caches,
    • the chipset (memory controller and I/O controller),
    • the system memory,
    • all PCI devices (by assigning bus numbers and resources),
    • the primary graphics controller,
    • mass storage controllers (such as SATA and IDE controllers),
    • various I/O controllers (such keyboard/mouse and USB).

    Finally, it loads the boot loader for the operating system, and transfers control to it. The entire process is known as Power-on self-test (POST). On the original IBM PC, the hardware only needed minimal configuration and POST was indeed used for testing; on modern systems, most of POST actually consists of hardware configuration.

    Once system memory is initialized, the BIOS typically copies/decompresses itself into that memory and keeps executing from it.

    Nearly all BIOS implementations can optionally execute a setup program interfacing the nonvolatile BIOS memory (CMOS). This memory holds user-customizable configuration data (time, date, hard drive details, etc.) accessed by BIOS code. The 80x86 source code for early PC and AT BIOS was included with the IBM Technical Reference Manual.

    In most modern BIOS implementations, users select which device boots first: CD, hard disk, floppy disk, flash keydrive and the like. This is particularly useful for installing operating systems or booting to Live CDs, and for selecting the order of testing for the presence of bootable media.

    Some BIOS's allow the user to select the operating system to load (e.g. load another OS from the second hard disk), though this is more often handled by a second-stage boot loader.

    [The BIOS Chip and BIOS Recovery

    ROM with BIOS
    ROM with BIOS

    Before 1990 or so BIOSes were held on ROM chips that could not be altered. As its complexity and need for updates grew, BIOS firmware was subsequently stored on EEPROM or flash memory devices. The first flash chips attached to the ISA bus. Starting in 1998, the BIOS flash moved to the LPC bus, a functional replacement for ISA, following a new standard implementation known as "firmware hub" (FWH). In 2006, the first systems supporting a Serial Peripheral Interface (SPI) appeared, and the BIOS flash moved again.

    EEPROM chips are advantageous because they can easily be updated by the user; hardware manufacturers frequently issue BIOS updates to upgrade their products, improve compatibility and remove bugs. However, the risk is that an improperly executed or aborted BIOS update can render the computer or device unusable. To recover from BIOS corruption, some new motherboards have a backup BIOS (i.e. they are referred to as "Dual BIOS" boards, Gigabyte even offers a motherboard with quad BIOS). Also, most BIOSes have a "boot block" which is a portion of the ROM that runs first and is not updateable. This code will verify that the rest of the BIOS is intact (via checksum, hash, etc.) before transferring control to it. If the boot block detects that the main BIOS is corrupted, then it will typically initiate a recovery process, by booting to a removable device (floppy, CD or USB memory) so that the user can try flashing again.

    Due to the limitation on the number of times that flash memory can be flashed, a flash-based BIOS is vulnerable to "flash-burn" viruses that repeatedly write to the flash, permanently corrupting the chip. Such attacks can be prevented by some form of write-protection, the ultimate protection being the replacement of the flash memory with a true ROM.

     Firmware on adapter cards

    A computer system can contain several BIOS firmware chips. The motherboard BIOS typically contains code to access fundamental hardware components such as the keyboard, floppy drives, ATA (IDE) hard disk controllers, USB human interface devices, and storage devices. In addition, plug-in adapter cards such as SCSI, RAID, Network interface cards, and video boards often include their own BIOS, complementing or replacing the system BIOS code for the given component.

    In some devices that can be used by add-in adapters and actually directly integrated on the motherboard, the add-in ROM may also be stored as separate code on the main BIOS flash chip. It may then be possible to upgrade this "add-in" BIOS (sometimes called an option ROM) separately from the main BIOS code.

    Add-in cards usually only require such an add-in BIOS if they:

    • Need to be used prior to the time that the operating system loads (e.g. they may be used as part of the process which loads (bootstraps) the operating system), and:
    • Are not sufficiently simple, or generic in operation to be handled by the main BIOS directly

    Older operating systems such as DOS, as well as bootloaders, may continue to make use of the BIOS to handle input and output. However, most modern operating systems will interact with hardware devices directly by using their own device drivers to directly access the hardware. Occasionally these add-in BIOSs are still called by modern operating systems, in order to carry out specific tasks such as preliminary device initialization.

    To find these memory mapped expansion ROMs during boot, PC BIOS implementations scan real memory from 0xC8000 to 0xF0000 on 2 kibibyte boundaries looking for a 0x55 0xaa signature, which is immediately followed by a byte indicating the number of 512 byte blocks the expansion ROM occupies in real memory. The BIOS then jumps to the offset immediately after the size byte, at which point the expansion ROM code takes over and uses BIOS services to provide a user configuration interface, register interrupt vectors for use by post-boot applications, or display diagnostic information.

    For UNIX and Windows/DOS systems there is a utility with which BIOS firmware software can be dumped at http://www.linuks.mine.nu/ree/
    There is a tool to flash the BIOS from Linux at http://packages.debian.org/flashrom

     The BIOS boot specification

    If the expansion ROM wishes to change the way the system boots (such as from a network device or a SCSI adapter for which the BIOS has no driver code), it can use the BIOS Boot Specification (BBS) API to register its ability to do so. Once the expansion ROMs have registered using the BBS APIs, the user can select among the available boot options from within the BIOS's user interface. This is why most BBS compliant PC BIOS implementations will not allow the user to enter the BIOS's user interface until the expansion ROMs have finished executing and registering themselves with the BBS API.[The Rise and Fall of the BIOS

    Older operating systems such as DOS relied on the BIOS to carry out most input-output tasks within the PC. A variety of technical reasons eventually made it inefficient—especially for more recent operating systems written for the Intel 80386 such as Linux and Microsoft Windows—to invoke the BIOS directly. Such operating systems instead used their own better-performing native drivers and were also much easier to extend to support new hardware. As such, the BIOS was mostly relegated to bootstrapping to the point where the operating system's own drivers could take control of the hardware.

    There was a similar transition for the Apple Macintosh, where the system software originally relied heavily on the ToolBox—a set of drivers and other useful routines stored in ROM—but later discarded this in favour of software drivers.

    In recent years, however, by way of systems such as ACPI, the BIOS has taken on more complex functions such as power management, hot swapping and thermal management. This has led to renewed reliance on the BIOS by operating system producers, and an increase in complexity of BIOS code. This in turn led Intel to develop Extensible Firmware Interface (EFI), a specification which defines the firmware which replaces the functionality of the legacy BIOS. EFI is now driven by The Unified EFI Forum, an industry SIG. Linux has supported EFI via elilo boot loader since early 2000. Microsoft announced that support for EFI in Windows Vista is only available for the 64-bit versions starting with SP1, and for Windows Longhorn.

    The Open Source community increased their effort to develop a replacement for proprietary BIOSes and their future incarnations with an open sourced counterpart through the LinuxBIOS and OpenBIOS/Open Firmware projects. So far, those projects have met with some success, with AMD providing product specifications for a number of fairly recent chipsets, and Google sponsoring the project. Motherboard manufacturer Tyan offers LinuxBIOS next to the standard BIOS with their Opteron line of motherboards. MSI and Gigabyte have followed suit with the MSI K9ND MS-9282 and MSI K9SD MS-9185 resp. the M57SLI-S4 modems

    The BIOS business

    The vast majority of PC motherboard suppliers license a BIOS "core", and toolkit from a commercial third party, which creates and maintains such a core. The motherboard manufacturer then customizes this BIOS to suit its own hardware. For this reason, updated BIOSes are normally obtained directly from the motherboard manufacturer.

    List of BIOS suppliers

     See also

    [edit] Sources

    [edit] External links

    [edit] Notes and References

    + نوشته شده در  چهارشنبه سی ام خرداد 1386ساعت 1:25  توسط beta  | 
     
    Video CD (aka VCD, View CD, Compact Disc digital video) is a standard digital format for storing video on a Compact Disc. VCDs are playable in dedicated VCD players, nearly all personal computers, most modern DVD-Video players, and some video game consoles.

    The VCD standard was created in 1993 by Sony, Philips, Matsushita, and JVC and is referred to as the White Book standard.

    + نوشته شده در  چهارشنبه سی ام خرداد 1386ساعت 0:37  توسط beta  | 

    Whether you're a novice or an expert PC technician, we've all had an experience when a new PC would not boot. There's no worse feeling than pushing the power button on the front of a new machine an hearing absolutely nothing. This article will focus on some of the common problems with new builds and help to reduce the computer troubleshooting time when diagnosing problems with your new computer.

    Take A Quick Visual Of The Computer

    You should have already done this before trying to power up the PC, but a lot of novice PC builders will skip this step in anticipation of powering up their new machine. This step may save you time and money. First, triple check to make sure the CPU is sitting flat on the motherboard socket. It's probably hard to tell because of the heat sink, but if the entire CPU and heat sink combo looks skewed, then chances are it's not installed properly. Next, go over the IDE cables and the thin wires running from the power and reset switches to the motherboard. While the IDE cables are keyed, it's quite possible to get those case wires backwards or completely. Lastly give the PC a little shake. Make sure an errant screw didn't fall behind the motherboard during the install. This could blow the motherboard or cause the system to go to ground.

    Computer Hardware Troubleshooting

    When a new PC will not boot, a good place to start is the power supply. Is the machine getting power? If there is no fan activity at the rear of the power supply, then the power supply isn't working. First, check the wall socket and power strip to make sure power is actually being supplied to the computer. If there is power to the outlet, confirm that the | / O lever in the back is set to |. Then confirm that the voltage is set to 110V in the USA or 220V in countries that require that setting. If you have a voltmeter, you might want to consider testing the power supply. Refer to the pin out chart for the correct power supply voltages .

    Troubleshooting Video Cards

    If the system powers up, but you get nothing on the screen, the video card may be the culprit. First, confirm the video cable is secured to the video card's output. If the motherboard has built in video, and you're using a PCI-E or AGP card, make sure the cable is secured to the correct port. Also, check for bent pins on the connector and confirm the monitor works and the brightness controls are set correctly. Do you hear any beeps? If so, refer to our BIOS beep code chart . It's always a good idea to reseat the RAM and video card when you get the "No Signal Displayed" message on the monitor.

    Dead Motherboard or CPU

    Improper installation of the motherboard and CPU can cause instant failure. We like to install the CPU and RAM modules on the motherboard before installing the motherboard in the case this is because it sometimes requires some effort to get the heat sink seated properly on the CPU. The CPU itself should slide effortlessly into place and lock without any problems with the lever. If you require resistance when installing the CPU, make sure the CPU's pins are properly aligned to the socket on the motherboard. Apply the correct amount of thermal grease or tape as recommended by the manufacturer, then install the heat sink. The heat sink should rest flatly on top of the CPU.

    As for the motherboard, refer to the manual about each of the connections to the case. A common problem area are the standoffs between the case and motherboard, and the connection of the thin wires from the power and reset switches to the motherboard.

    BIOS BEEP Codes

    You will often receive a BIOS beep code when there is a hardware issue with the PC. You should determine the BIOS residing on the motherboard by physically looking for the BIOS chip on the motherboard. Look for something like AMI-BIOS, AWARD BIOS or PHOENIX. Refer to our BIOS Beep Code Chart when diagnosing beep code errors. This will often lead you quickly to the source of the hardware problem.

    In Conclusion

    While these new computer installations can be frustrating, it's important to take a step back and think before you do more damage. Take a nap or a walk and then look at the problem with fresh eyes. If you need further assistance, please consult our techs on our message boards .

    Authored by: David .
    Click Here to View all the questions in PC Troubleshooting category.
     
    + نوشته شده در  سه شنبه بیست و نهم خرداد 1386ساعت 5:2  توسط beta  | 
    PartitionMagic
     
    PartitionMagic
    PartitionMagic 8
    Main window of Norton PartitionMagic 8.05
    Developer: Symantec
    Latest release: 8.05 / 2004-05-05
    OS: DOS, Microsoft Windows, WinPE
    Genre: Disk partitioning utility
    License: Proprietary
    Website: www.symantec.com/partitionmagic/

    PartitionMagic is a computer program for hard disk drive partitioning originally made by the PowerQuest corporation but now owned by Symantec. The program runs on Microsoft Windows operating systems or from a bootable CD-ROM and enables creation and modification of partitions. Existing partitions can be resized without loss of data.

     

    PartitionMagic is capable of resizing NTFS or FAT (16 or 32) partitions without data loss, and can copy and move partitions, including to other disks. It also has various other features, including being able to convert between FAT16, FAT32 and NTFS, modify the cluster size of FAT16/32 and NTFS filesystems, and merge adjacent FAT or NTFS filesystems (all without data loss, though some NTFS-only metadata is lost on conversion to FAT). Additionally, it has somewhat limited support for ext2 and ext3 partitions.

     

    PartitionMagic, while under PowerQuest, was updated regularly, adding new and useful features. Since Symantec purchased the application, there has not yet been a new release, and Symantec has stated that it has no plans on releasing a new version.[1]

    [Compatibility issues

    PartitionMagic is compatible with Windows NT, 98, ME, 2000, and XP desktop editions.

    It fails to run under Windows Vista. When launched, with a Windows Vista partition present, even from another version of Windows, Partition Magic displays the following error: "Init failed: Error 117. Partition's drive letter cannot be identified."

    When run on a server edition it displays a dialog box reading "PartitionMagic cannot run on Windows NT/2000/.NET Server.".

      

     

    + نوشته شده در  یکشنبه بیستم خرداد 1386ساعت 6:19  توسط beta  | 
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