USB Ports Won't Work After Reinstalling Windows XP

Sorry for double posting but I wasn't sure if this would be considered a software or hardware issue...

A few days ago I reformatted my HP NX6325 because it was running slowly. After reinstalling Windows XP, only 1 of the 3 USB ports would work -- the one where I plug in my USB mouse. When I tried to plug in my web cam, the power light came on but it wouldn't work. I looked at Device Manager under USB devices and it said there was an unknown device. After uninstalling each USB device, I rebooted and then 2 of the 3 USB ports worked so I was able to use my web cam. Unfortunately, after I restarted my computer, none of the 3 USB ports again. I tried the same step above -- uninstalling each USB device in Device Manager and rebooting -- to see if Windows would find the devices, which it said it did, but it still says there's an unknown device and none of the 3 ports still work! I can't even use my USB mouse anymore and have to use the touch pad. I only bought this laptop just over a year ago and hope it's not the motherboard... GRRRRRRRR

Thanks in advance for any help...

Steph

 

I installed SP2 and all other updates as well as the drivers. I think I'm going to take it to the shop because I think it may have to do with the motherboard...

Thanks for the suggestions and your reply!