i have to say that Dell's with NVIDA, Like the D630, have NVIDA embedded video that has a flaw that Nvida tried to hide from Dell. The video processor would heat up, supposidly would call for the fan to come on or go to a higher speed...it didn't, that is the flaw. After a year or so of overheating it takes it's toll, pixelated display, color bands, split screen...etc.. I have replaced close to 100 mainboards of defective D630s for our clients, it is starting to show in the D620s and D830s also..not Dells fault. If it were me, I would make sure that this is not something across the board with all their video processors and just an isolated issue with Dell.