I have been having this problem for a few weeks now. My usb devices will all just randomly stop working and I can do nothing on the pc. The only way to get it working again, is rebooting it. The time of when this starts happening varies anywhere from 1hr, to even 4hrs or later. I updated the BIOS, replaced my mouse (I thought it was the mouse), got a new power supply, disabled the USB suspend in power savings... I feel like I have tried everything. I am thinking that it could have something to do with the motherboard, and thinking of just buying a new pc in about two months, if this current one can last me this long. I have an HP p6310y that is about three years old now. I heard that the mobo in this model can be faulty as well...