[WIN7] 64 Home Premium & usb drive issues

[kenmo]

One of my Windows 7 Home Premium computers (The motherboard is an Asrock Wolfdale1333-D667. The chipset is Intel 82801G ICH7 USB family)... is having a devil of a time recognizing usb thumb drives. Sometimes it will recognize the thumb drive when I first insert it but reading files or navigating the thumb drive is slow.. If I eject the thumb drive and insert it again or another thumb drive it'll come up as unrecognizable...

I've even tried an external usb 250gb hard drive and the same problem.

I thought it may have been an issue with my usb on the motherboard or case so I attached my usb dvd burner and it worked fine. I plugged APC UPS into one of the usb ports on this computer and it was recognized instantly...

Windows 7 Device Manager doesn't show any hardware problems with my usb...

I've also tried these thumb drives on my 3 other computers ( two Windows 7 Home Premium and one Ubuntu 10.10) and they worked as designed...

Also to make sure it's not an hardware issue I booted up the offending computer with an Ubuntu 10.10 live cd and it had no problems with the USB devices...

I have this computer sent up as a server for my 3 other computers so I really don't want to re-install Windows 7 unless I really have to..
I should also mention I have two printers connected via usb to this computer and there are no problems printing from this computer or the client computers...

I've also deleted the usb devices in device manager and rebooted the computer which re-installed all the usb ports but still it's not working...

My motherboard has the latest bios and drivers...

Any thoughts?

Thanks kindly...

Ken