i have a sony vaio PCG-GRT170, came with Xp. i recently installed vista and didnt really care for it on my laptop, so i went back to Xp professional. now my usb drivers arent there, and im getting an error message that i have a hi speed usb device plugged into a non hi speed hub. this is for my external hdd, now what i dont understand is why did it work before, and now it doesnt. sony support cant seem to help me, and all they can tell me is that it wont work because its 1.1 usb, not 2.0. BUT IT WORKED YESTERDAY when i had vista installed, and it also worked before i put vista on. please let me know if you have an answer.
Does your copy of XP have any service packs pre-installed? You may need to get those again. Also bear in mind you may need to reinstall your chipset drivers.