I recently bought a new video card and everything worked fine until a few days ago when the video suddenly became sluggish. This causes my games to lag and even to crash my PC at some points. Games like Tomb Raider Anniversary, which uses heavily the video card, give me a lot of trouble I also canīt play any dvds or videos stored in my pc. When I start Windows Media or the dvd player the videos seem to lag or or get stuck only to resume a few seconds later. I tried to uninstall and reinstall the drivers of the video card but everything remained the same. I also tried to update the drivers to the latest version but the result was the same. I also noticed a trojan in my pc and removed it. Is this lag caused by software issue like the trojan or a faulty video card? Currently I have Windows Vista Ultimate edition 32bit, Pentium IV with 3.06 GHZ, 1536mb of RAM and AGP VisionTek Radeon HD 2400 Pro.