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PC System Fails CPU Test

Failed CPU Test Error Message

How many times have you had your computer freeze with the message System Failed CPU Test appearing on your monitors screen or even spoken to you through your speakers? Hopefully never, because it can be a difficult task to track down the reason for this error message.

There is a ton of advice on the Internet but basically there is a set routine to try. First, don't assume that your PC's CPU is at fault. In fact this is very unlikely.

This error message occurs during your computers boot up process (the POST routine) when all the main hardware components are being checked.

Bearing this in mind, the best way to proceed is to start checking the usual suspects which include one or more of the following: power supply, CMOS battery, keyboard, graphics, motherboard, memory and any number of electrical defects causing the shorting out of a component.

The steps - (always try the simplest ones first).

1. Try resetting the CMOS. Remove the CMOS battery, wait for 30 minutes or so, and then replace it. If your PC is a few years old it's better to buy a new CMOS battery (buy a 3 volt CR2032 battery from Amazon UK or any Boots store - other shops may sell the DL2032 3 volt battery, which is in fact identical).

See if the PC boots successfully.

If not,

2. Try removing and replacing your memory module to see if this solves the problem. With more than one memory module try removing them all and then try each one in turn, as one may have failed.

If fitted, you should also try to check the AGP or PCI video card by replacing it with another one, preferably a simple straight VGA card that is known to work.

Make sure all your hardware components are firmly seated in their respective positions on the motherboard.

After you have checked these general things see if your PC now starts up.

If not,

3. Try a new Power Supply (see Power Related Problems)

It's best to borrow one if you can just to see if this is the problem. You should verify that the borrowed (or purchased) Power Supply Unit meets the requirements of your motherboard and processor.

Once fitted try switching on your computer. If you still get the same error message try the next step.

Now Test the Motherboard

4. If your computer is still refusing to boot you should strip your PC down to just the motherboard and CPU/heat sink.

It's often best to remove the motherboard from the motherboardcomputers case to rule out any electrical problems e.g. your motherboard could be shorting out because it's touching the case. You should wire up your Power Supply, your hard drive and plug in your speakers and monitor so you can see or hear any error messages or beep codes.

Now see if your PC boots successfully.

If it does boot up successfully the problem is no doubt your motherboard not being properly positioned in the computer case. It must be placed on risers and must not touch any part of the case otherwise it will short out and produce an error message as the PC begins to boot.

If the problem persists even when the motherboard is removed from the case it is highly likely that this key component is damaged and needs replacing.

Unfortunately the only way to be sure that the motherboard is the culprit is to test the motherboard in another computer, or try another motherboard in your computer. If you don't have spare parts to do this repair you'll probably have to find a local PC Repair shop to help you. Alternatively, check out our Easy PC Repair Guide.

The same problem occurs with testing the CPU itself. The best way is to try your CPU in another suitable computer. Or get hold of another one and see if it works in your PC. This test has been left to last as it is unlikely that the CPU is the cause of the error problem unless your PC is older than 4 or 5 years and has been placed in a very dusty environment - see 'Cleaning your Computer'.

If your PC now boots successfully all this effort has been worth it!

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