Sorry for hitting a old post, but, I see that no one really answered this.
To update a Gigabyte motherboard bios with little pain, use their @bios program. You first want to download the bios you're intending to use, then unzip it. When you run the program, select the unzipped bios file.
Before doing this, insure that your system is stable. It might be a good idea to go into bios first, and set it to default, since it will reset your bios anyway.
I've used this feature a few times over 2 GB mobos, and never had a issue.
***I've got that same mobo, if it is Rev 3, like mine, then you should update to the latest beta bios. It will give you control over "APM". My version of that mobo would throttle my FX8320 at stock settings with the bios it came with. Now, it's a good oc'er (for the most part).