USB ports cause XP crash - help!

Hey ya'll, can anybody tell me what causes a friend's computer to crash when something is plugged into any USB port on the machine? (flash drive, WD60 pocket drive, USB external hard drive, all in good working order) It doesn't matter which port you use, 4 on the back (right on the mb) or 2 in the front, it immediately crashes XP home sp2. Otherwise the machine is fine, and a USB mouse works normally. It's a 2.4 celeron, 256 ram with 16 shared video (moving her up to 512 with another 256), 80 gig drive with only 10 gigs used, secondary case fan so heat is not the issue, does it cold or hot from all day run. I added a PCI card with 2 additional USBs and it works fine. All hardware shows operational in device manager... this thing's got me bumfuzzled

 

Hi, and welcome to Major Geeks (your first post?). :cool

If the PC is still under warranty I'd recommend getting it straight back to the seller. It sounds like there is a dodgy electrical connection between the USB ports and the motherboard, to me. Bazza

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