My PC with the Abit KT7A mb and duron 900 cpu worked well for about 2 years, but has later started having random lock-ups. Also sometimes when I tried to open the cd-drive it stopped in the middle for a sec and then continued opening. Seems as if it had something to do with power. It quickly kept getting worse and worse, and now it won't show anything on the monitor, usually. Nothing happens when I turn it on, other than the PSU and CPU fans start spinning. Sometimes (rarely) I can get to the bios, but it will lock up after less than 30 seconds.

I've tried to swap all other parts...