I wasen't sure where to post this, so if im in the wrong place, sorry.
Here goes, Im having a weird pc problem, it started about a week ago when my computer simply stoped in its tracks (power is still on but the screen just goes black, the screens power light is still on but its like its not getting a signal from the pc.)
The next day it started happening every couple of hours or so, and its been getting worse ever since. Now when i turn it on the screen goes black right after the "windows xp loading" screen with the black backround. It does the same thing in safe mode.

First i tought it might be the video card, so i tested it on another pc and its fine. So i figured it was software related, so i tried reinstalling windows. It boots from the cd just fine, but when i get to the regional settings dialog it does the same thing again.

Can anybody help me with this, or can someone tell me what i should be looking for.
The pc is a dell minitower with windows xp sp2 installed. All of this started about 2 days after i instaled a new dim of ram.