Some time ago the USB ports on my Chaintech VNF3-250 stopped working. I do not recall changing anything on the computer when this happened. I have re-installed windows and played with any bios setting i can find. I checked the device manager and it does not show any errors for the USB ports. For now i am using a PCI card for my USB devices but my Dell DJ will not work with the card for some odd reason so i need to fix this problem. Any suggestions?