I think i have a similar problem. When i reinstalled windows 7 x64 (about 5 months ago), everything was working fine. But about 3 months ago, my usb ports started to behave weird! I have my usb mouse and usb soundcard connected to the computer since i reinstalled windows 7, and they are still working fine, but if i plug a new device in the computer, windows says "usb device not recognized", but there are some new devices that works fine. I though it was a problem of my internal usb hub, so i bought a usb hub and it works, i plug a device in the hub and everything works fine, but if i plug the same device directly in the computer, windows says "usb device not recognized"! And i don't like the usb hub because it is USB 1.1 and some devices i have, need to be plugged in a USB 2.0 port. I really need help on this!