About a month ago I started noticing small white dots appearing on some video files I had. On others it was green and pink lines. On some it was just noise distortion in the video. Now, I am not an expert but I am also not a true novice and it was obviously a codec problem. I cleaned my system of my video codecs and started fresh only to have the same thing happen. I also reinstalled DirectX to the same avail. I tried several other methods of resolving the issue and all lead to nothing. I then swapped video cards out as well as ram, still the same. This led me to do another clean install of WinXP to see. I reinstalled XP and the first thing I did was head to Microsoft’s update site. When I got there with IExplorer this is what I saw: http://dsusinfonia.com/video/Microsoft%20DirectX%20Site%20-%20IExplorer.JPG (That is the DirectX site, but is the same thing I saw at the Windows Update site). Even more confusing is that with Firefox, the same site appears as: http://dsusinfonia.com/video/Microsoft%20DirectX%20Site%20-%20Firefox.JPG I proceeded with all of the steps I normally do on a clean install of XP and still video and now some images are distorted. I tried disabling hardware acceleration and it also did nothing. I then tried various video players and it got even more confusing. Windows Media Player 10 would actually play some of the videos fine, others would have some distortion, and still others would be horrible. VLC plays everything completely distorted, as does Windows Media Player Classic. I used GSpot to try to find a pattern of file types and codecs that were worse than others, but there really does not seem to be a pattern. Sometimes the distortion is white noise, sometimes it is colors and smears, other times it might be completely distorted. One example of the most common is http://dsusinfonia.com/video/Bond%20-%20Windows%20Media%20Player%2010.JPG. I am completely stumped because my problems are all easy to diagnose on their own but none of the known fixes are working. Any ideas?

EDIT: CPU has been swapped and checked as well now.