It does't really matter what I had suggested two years ago, a lot have changed since then. Now, I would recommend for you to download the latest SPI/BIOS update from Gigabyte and follow the CleanUp Guide. Then flash the new SPI/BIOS image with the in-BIOS flasher. That way we know that the ME firmware region is healthy and properly configured. So the rest are BIOS-related, including MEBx and its own configuration settings.