Downgrading a preinstalled vista pc to xp is the worst thing you could ever do to a pc! A vista preinstalled pc includes all the drivers to run vista smoothly. If you downgrade, the brand's special features, quick launch buttons, and webcam/microphone won't work. Sound, video, networking, and bios will run at limited functionality, if you can even find the drivers, which can take weeks at best. So think, would it be worth the trouble to downgrade and lose a lot of features for a few applications and games? Also consider the fact that in a few years, updates and support will end for xp. Also, all new applications will be made just for or designed mainly for vista. If you downgrade, you're basically putting your self in an enclosed circle that can't open up very far. So its your choice, but microsoft, hp, dell, acer, compaq,asus,and all the other major pc makers as well as I recommend to stick with the preinstalled vista.

Don't give microsoft more cash than they need.