[flyinghamster]

On the other hand, 64-bit XP wasn't really ready for prime time. Back in that era, I built up a system and was originally intending to run XP64 on it - until I read about its poor compatibility with the 32-bit world (especially drivers). I wound up returning the unopened XP64 and got 32-bit instead, which turned out to be the right call.

[yuhong]

In retrospect, adding PAE support to XP SP2 would probably be less risky (though would still require new drivers).