I have a computer that does not post. The PSU tested fine so I can only figure it's the motherboard or the cpu. Is there any way to distinguish which one is causing the problem. The lights on the mobo do turn on but I've seen boards fry processors and visa-versa so I am very causious. Any advice would b greatly appreciated.

Suspect the memory too.
Any beep tones?
Also, nothing in the LEDS can also be an error indication. Refer to your MB's documentation.

I have a computer that does not post.
No post beeps at all so it can't be RAM. All the LEDs light up. The ones on the board and the ones on the front of the computer. It just doesn't post.

Sorry, your previous statement is not correct. It kind of depends on the make of the MB.
Please reply with the type of the motherboard (or the type and model of the computer, if it's a brand name), and the BIOS type (you'll find a sticker on the chip for that - look for "award" or "phoenix" or "AMI").
All LEDs on and no beep can be due to the CPU, or the memory, or yes, the MB itself.
All LEDs on is usually the very first step of the POST. That is where it tries to determine the size of the memory. And it will fail if either the MB, the CPU or the memory is defective - or missing.

Additional info:
The example in my previous message was for a desktop from "Digital".
If the MB is an MSI board, the LED code means that the CPU is defective or not properly inserted.
Oh, BTW, there has not been tampered with jumper settings I hope? If not sure, put the jumpers for the lowest speed.
Also, ensure that the "clear BIOS" jumper is set for normal operation.
(better review ALL jumper settings).
As you can see, no POST (or POST stuck at the very first step) can have a lot of causes.

No post beeps at all so it can't be RAM.

Usually, but not always. I have a few absolute junk motherboards that don't even bother to beep if no RAM or the wrong RAM is inserted. (Check your motherboard manual, just to be sure).

As far as I know, if your board doesn't provide any useful facilities to diagnose CPU problems, your kind of stuck. I was in a similar situation and just tried another motherboard with my CPU, and didn't fry anything...

Good luck
~psi42

If it's not posting anything at all, it's the mobo that has the problem as you should at least get the bios info before the system even tries the cpu or RAM or anything else.

Do you get the bios post?

Beeps for Error.

To keep the peace,and without throwing a 'wobbly' (English expression?)

these are the beeps for error which may drive you nuts!

No beeps
Short,no power,bad CPU/MB,loose peripherels

One beep
Everything okey!

Two beeps
Post/CMOS error

One long/one short beep
Motherboard problem

One long/two short
Video problem

One long/three short
Video problem (again)

Three long beeps
Keyboard error

Repeated long beeps
Memory error

Continuous HI-LO beeps
CPU overheating


And there you have it.

Happy beeping,
Nez. :D

How can you find out what's the highest speed of a processor your motherboard can take? How do you find that out without opening your computer? I have windows xp, I don't know which mother board I have, please help me out!!