Computer turns on and off in 1 second

[drbari]

Hi
My computer (which I built about 6 years ago) was overheating. So I opened it up, dusted it and removed the heat sink to check the silver. I re-silvered the heatsink and reinstalled it. When I turned on the computer, all the lights came on, the fans start, and the harddrive starts, but 2 seconds after powering up it shuts off. Any ideas?
Thanx

 

[jsc]

Go through all the cables and make sure they are connected.

It's unlikely that something coincidentally failed while you were cleaning, but it is possible. In that case:
Our standard checklist and troubleshooting thread:
http://www.tomshardware.com/forum/261145-31-read-posting-boot-problems

 

[drbari]

`Hi followed checklist....everything seems fine, but it still turns on for a sec and then turns off. Any other suggestions?