My GA-X79-UD3 is v1.0 and has BIOS F11. The problem started when I upgraded the graphics card to a new Gigabyte GV-N680OC with 4GB VRAM. The first power up after install resulted in a long (about 2 minutes) wait on the POST screen and then Windows loaded. I proceeded to install the drivers and tested the card on a flight simulator and it performed flawlessly. In an attempt to resolve the long boot, I tried to access BIOS but it will not let me, even with an old AT keyboard. I then proceeded to clear the CMOS settings by following the procedure on the manual (short the indicated two pins on the motherboard with mains disconnected). After that it refused to boot at all with the new card. Only displays the POST screen for a few minutes and then goes black with a flashing cursor. Will not let me access BIOS. I then proceeded to install the old card and was able to access BIOS and load optimized settings; but after installing the new card back it will not boot as before.
