First go to the Gigabyte site and download the BIOS you want to flash. Format the USB stick if its not yet. Then proceed the download BIOS from gigabyte. Run that file and extract that to your USB stick.
Now on to the BIOS.
In Set Utility - Standard CMOS Features screen view - the following settings
Drive A = NONE
Floppy 3 Mode Support = DISABLED
Be sure that on the third image below where it says "Legacy USB Storage Detect" is enabled.
Restart the computer and boot it off from there. It should run and flash. After flashing, Clear CMOS and Load Optimize Settings. Then save your settings and reboot. You should have successfully flash your BIOS.
