Hi. I have been having recent troubles with my machine (namely graphics). After a format of my system, and a lot of searching on the internet, I have come to believe that my problem is with either my system RAM or my video cards (geforce ti 4200) RAM. When I play games, the system will lockup and there will be various strange patterns on the screen. When I run DXDiag, using DirectX 7 interfaces, it works fine, but 8 and 9 fail miserably. Can anyone confirm or deny this? Also, if it is a video card problem, can help me figure out if/how to replace it (it is a PNY vid card)? Any help will be greatly appreciated.