i was wondering if anybody has had this problem or knows what to do about this. i'll reinstall (completely format) windows XP, install my basic programs, and about 2 to 3 weeks later, the computer will start having really bad lag problems. this has happend 4 times already. i have mcaffee virus scan, blackice for my firewall, i have adaware and spybot. there is no need to defrag the HD. in the Taskmanager, there are no programs hogging the CPU or the ram. SP2 is installed, but even uninstalled, the lag is still there. there is no clear time when the lag starts, no program will really start it. i keep reformatting but its really getting annoying now. if someone could help that would be great. TIA