Okay I was experimenting with OCing my board (same as you have) and my USB ports did the same thing. Whenever I checked my Device manager, it would say "unrecognized item" or something like that (I also got the little pop-up in the system try advising me to disconnect and reconnect the USB item). I did most everything you did (short of the format and window re-install), tried all the usb ports... all dead. I reflashed the bios with the most current (just to make sure) - nothing. Reflashed with the original (shipped with) bios - nothing. At this point I had the wierd problem with my video card again (for some reason this board had a problem with the 3.0 & 2.0 settings - had to manually set them) so I cleared the CMOS. Upon rebooting - USB is working again! I then flashed the BIOS back up to the current level and all seemed fine. Until the machine started "blue screening" about every 6 hours, so I did the obvious and started with a fresh install. Still does it. I got tired of playing with it so I finally did a RMA back to NewEgg.com.