It certainly does not sound like a CPU problem if your trying different ones. If there was something wrong with the CPU you wouldn't make it to POST.
What operating system are you using by the way?
Causes -
There are many reasons for a computer to stop working. However, it is usually because all available resources have been used up, or a program or piece of the connected hardware has caused it to freeze. Generally, it will be because of one of the following scenarios: the RAM (on-board chip memory combined with the paging memory) has been used to maximum extent or the CPU (central processing unit) is at 100 percent. In other words, the processor or memory is working so hard that nothing else can work. Other causes include a badly written driver for an accessory, outdated or inappropriate drivers.
Here are some common freezing causes you may wish to look into:
Low memory
Low disk space
Fragmented disk
Too many programs open simultaneously
Corrupt files
Software bugs
Virus infection
Overheating - random lockups that start several minutes after you start up the PC are often the result of the processor cooling fan not working properly or other cooling issues.
Other Reasons For Freezing
Your computer's memory chips may have worked loose. This is more appropriate to a desktop than a laptop, since the memory chips in a laptop are held in tightly in place with spring-loaded guides. However, check this if the laptop has suffered a severe fall. Memory chips should be cleaned and reseated, because this is a common reason for freezes on a desktop computer.
Another reason for a computer freezing is that you have plugged in too many peripheral devices, such as controllers, cameras, scanners and printers. Usually, this problem will cause the computer to fail to boot (start) correctly. .
A blue screen of death, can tell you a lot about what is wrong by looking at the numbers after the word, "STOP." For example, you will see a code such as 000X000000. These numbers identify what is wrong, and you can check online to see what the stop code means. However, these blue screens are most often because of bad device drivers, hardware elements which have gone bad or software that has been installed. You will need to boot in Safe Mode, and then, by process of elimination, remove and replace suspect drivers or hardware, to determine what is causing the freeze.
Think back to the last thing you did before the freezes began (?) If nothing drastic and if your RAM is seated correctly, the first place to start would be to test your memory.
See rshaffer61's excellent advice on how to do that in post #2 here:
http://www.geekstogo...keeps-crashing/
Edited by Akabilk, 21 November 2011 - 04:46 PM.