CPU Wont post

[Omoobhs]

ok, so my pc wont post this morning- I am wondering if anyone can offer guidance to confirm my fears.

I get a single click sound (not sure from where) when I power on the motherboard, but nothing powers up. The Motherboard power light is on.
I have tested a few things (PSU, gfx cards) but the point that concerns me is this:

When I unplug the CPU 12v the motherboard powers on fully but I get a cpu error LED (as expected). But this atleast tells me roughly where to continue my hunt.

As I have tested this same symptom with another PSU.

Does this indicate the CPU has given up?

Any advise, opinions, all appreciated.

[Omoobhs]

Ok - It's not the CPU (phew)

Which leave me with it being a short or a Motherboard fault I think.

[SuicideNeil]

Try the mobo out of the case to rule out a short-circuit issue ( unlikely given it's been fine up until now however).

Click sound is probably a relay in the PSU- does it do this with the other PSU?

If you have another mobo to test all the other components with, that would be handy..

[Omoobhs]

Thanks for the reply!

I have tested with a different PSU and get the same symptom.

The whole setup in on a test bench at the moment, although it was before the issue started so I will remove it this weekend and see how I get on.

I currently feel this is going to be a short on the mobo or a actual motherboard failure of some sort. Will post back this weekend with the outcome.


Cheers!

[Omoobhs]

So, it continues...

I purchased a new CPU & motherboard.

- I tested the new CPU in my old motherboard to rule out the CPU, had the same symptoms as the original fault.

- I then swapped out the motherboard & re-tested, again with the new CPU. The motherboard turns on which was good to see, but the CPU_LED is on constantly and is red and it does not post.
Tested with my original CPU in the new board - same result.

Checked both boards for bent pins - all straight & tested different PSU's each time, same outcome.

Now my concern is that my old motherboard probably died & took the original CPU with it. When I tried the new cpu in the old board, I think it killed it.


Does this seem likely?

[SuicideNeil]

CPUs tend to be hard things to kill, even after power issues, though I suppose it is possible- have you ruled out the RAM yet though?

[Omoobhs]

Have been testing with 1 stick since I started this one, not used all sticks yet though so will check. The mobo has a RAM test which shows no fault when I tested with all the ram installed, but it's a logical point.

Found out this afternoon that there was a power cut the night before this failed to boot so thinking it got surged at the moment.

Thanks for the reply, more testing tomorrow...

[Omoobhs]

turns out the motherboard had fried in a power cut and became a CPU killer.

New board & cpu - system up and running, just a shame I killed 2 cpu's in the process.