Well no one seems to be to distressed about the outcome of this thread.
I will add my final words. The USB3 controllers on my motherboard are the cause of all my issues and it came to light when I tried adding Hyper-V to my Win 8 Pro install. The system would hang and then I would have to restore it back to pre Hyper-V activation.
After much searching I have found a number of links with the same or related problem.
Here is a link to Microsoft which states that Gigabyte systems have a known issue with the USB3 controller.
http://support.microsoft.com/kb/2693144I have reverted back to F12 on my system and my USB3 ports are functioning. However if I want to run Hyper-V I will need to disable the onboard USB3
ports. To have USB3 ports available for use on either bios version and with Hyper-V installed a purchase of a third party controller is required.
This seems like an unsatisfactory solution considering that the mainboard specs indicate 4 USB3 ports. I have corresponded to Gigabyte support but of course they can't duplicate the problem. They did recommend completing an RMA request but I am hesitant to do this until they admit that there is a known issue to this problem.
I would like to add that my MB serial number starts with 1148 this indicates the year and week of production and I was wondering what production dates other people had, who are experiencing similar issues.