Did I crack/damage the CPU core?

[Zincq]

I bought a new heatsink for one of my computers and decided to use the old heatsink in another computer. Switched out the heatsink and power everything back up - except that when I did so, the computer turned on for about a second and turned off again. Turned it on a couple more times, and the same thing happened - went on for about a second and turned off.

I unplugged everything and left just the motherboard and PSU connected together. Powered it on and it stayed on until I turned it off myself. I put the CPU back in and placed a HS on top. Powered it on, and yet again it stayed on for only a second. I tried reseating the CPU a couple more times, but each time the same thing happens. It works when the CPU ISN'T in the motherboard, so I'm starting to think that maybe I had damaged the core somehow. Am I correct on this or is there another reason why this could be happening?

It's an AMD Duron 800 - yeah, old CPU, I know.

 

[Gnosis]

hard to tell really, put the problem is somewhere around the
cpu/heatsink/motherboard. that's for sure.

First obvious and stupid question: did you use thermal-paste when
you mounted the heatsink?

Next onto the more serious stuff:

1. If you unmounted the motherboard from the chassi it
could very well be the motherboard intead of the cpu
that is broken.

2. IF the cpu is broken many BIOS:es has a error message
for that. check that up.

3. IF the cpu is broken you can often see the damage with
the help of a magnifying glass or such. Usually it's one of
the corners.

4. You did leave your RAM in the motherboard right? most
motherboards won't boot without it. None of mine does
anyway.

5. Double check so that you didn't break or short-circuit
anything when you mounted the heat-sink.

 

[Zincq]

Yes I did apply thermal paste.

Thanks for the suggestions.. I didn't unmount the motherboard, so I'll look on the CPU tomorrow - kinda tired now.