While it is backwards compatible, it is not natively supported in Win7, and requires a driver. That is why I asked if it was in a 3.0 slot, you would have to wait for Windows to load the USB 3.0 driver before the keyboard would work. I ran into this with a case mod that I was doing, I had a thumb drive and a keyboard in the 3.0 slots, and windows would freak out trying to install, figured that part out, then plugged the keyboard back into the 3.0 slot and I could not log into windows. Plugged back into the 2.0 and it would work, once the 3.0 drivers were install the problem went away completely.
Sounds to me like its not a BIOS issue, as the keyboard is working in the BIOS section, it sounds like a corrupted driver install, as when you plug the keyboard back in it works, that indicated windows is reinitializing the driver. Does it do the same in all the slots? If you are running off the front ports try a mobo hard wired port. Also you are not using an add in card to run the keyboard are you?
Which board do you have, that is not a valid model number, it will be a Z77MA-G45 or Z77A-G45, and they both have BIOS updates, the Z77A had one released on 5-9-12?[/quote]
OK, sorry my fault, I wasn't clear. When the keyboard is not working, it is also unresponsive to getting into the BIOS too, so nothing works at any point (when it's giving me problems). It's been a couple days and so far it's been fine. I'm hoping it's OK....still not sure what the problem is/was because I did nothing different. I'm thinking it is BIOS related since it's doing this at the very beginning. I wish there was a BIOS update cause I'd definitively do that. Oh and the mobo is a MSI Z77A-G45 http://msi.com/product/mb/Z77A-G45.html