my computer no longer works (at all). I need help

[maximo12]

I'm going to build a new computer but I would also like to get my old one running again.

my old computer's specs:
athlon xp 2000+
gigabyte 7vrxp
512 pc2700
geforce 4ti 4400

My problem: A while back my computer started to reboot randomly (not turn off- reboot). It seemed to do it when I was doing intense stuff on the pc. So, I thought it was a cooling issue. I did everything to cool it down and it still was rebooting. After a while, it would reboot even when I was away from the computer. I made sure all the cables and components where connected properly. I ran a virus scan, I checked all the settings in the bios, and it would still reboot during these operations. I thought it must be the power supply. I ordered a 480w Thermaltake power supply from newegg. And, guess what it still rebooted. Actually I thought it was fixed but after 20 mintues it rebooted again. I almost went crazy. This time I unconnected everything and reconnected them back and now it doesn't do anything when I press the power button. Nothing!

What could I replace to get it going. And what was the problem. My guess is the mobo but after what i've been through I have no idea. I had the system a little over two years when it happened.

 

[DanDrop]

Do you have a spare RAM that you can replace and check the sytem with? I had an old comp that gave me BSOD's/reboots etc. Turned out it was bad RAM.

Reset CMOS and Try reseating all components (vid card, ram, all molex cables, IDE cables etc). Make sure that the power switch header from case is connected to the mobo properly.

Most reboots are caused by heat/power problems. Are you sure that the CPU/Heatsink have enough cooling power? Maybe try re-installing and re-applying thermal grease on the HS/CPU?