I don't know if you've solved this yet but let me clairify my earlier point. If you make a move from an intel chipset to a via chipset you may encounter problems. Many of the drivers are different (that's why we load the 4in1 drivers as soon as windows is loaded). If that's your situation, then by all means backup your files and reformat, then load appropriate drivers, and update all other drivers as well (video, sound, NIC, modem, etc.)