You can updaet the BIOS on an ASUS X99 E WS 10G motherboard using the ASUS EZ Flash 3 utility. Go to BIOS > ASUS EZ Flash Utility under the Tool Tab in the Advanced View (F7). It has an “update via Internet” feature.
Instead, you can do it via USB and the BIOS_FLBK button:
- Download the BIOS update here: ｜｜ASUS USA
- Unzip it, copy the contents to a USB and RENAME the .CAP file to X99E10G.CAP.
- Plug the USB in to the system when it’s plugged in but turned off.
- Press and hold the BIOS_FLBK button (see number 12 on attached image) until the LED next to it stops blinking.
- Start the system.