Windows 10: Understanding the UEFI BIOS Gigabyte H81M-S for Windows 10 Pro x64

Hi, This is my very first installation on UEFI

I wish to install Windows 10x64 using UEFI and GPT on my brand new SSD. I have Windows x64 bootable iso already downloaded via media creation tool from MS.So now I have a bootable DVD/USB.

My Gigabyte MB H81M-S has UEFI bios(F2, latest available on Gigabyte site) and I found three combinations.

A. OTHER OS
With
UEFI and Legacy Boot, UEFI Only and Legacy Only, etc.
Here all the available boot devices are displayed in the boot sequence. (Legacy and UEFI Prefix)

B. Windows 8/ 8 WHQL
With
Added Option of CSM Support.
When Selected CSM Support as "Always" I get all the same options that I get in OPTION A (OTHER OS)
In addition, I get the Secure Boot menu. Can be turned on/off
Here all the available boot devices are displayed in the boot sequence. (Legacy and UEFI Prefix)

C. Windows 8/ 8 WHQL
With
CSM Support selected to "NEVER"
I get the Secure Boot Menu only. That can be turned on/off.
Here only UEFI Prefix Boot Devices are listed in the boot sequence.

Now, practically settings in option A and B look identical. How are they different in their implementation except for the Secure Boot feature?

Secondly, if I wish to install a fresh Windows 10 on brand new SSD in UEFI and GPT mode, all three options should achieve what I wish i.e. Win10 in UEFI mode with GPT disk, right? (of course, I will have to boot from UEFI prefix device in option A and Option B)

So, if the above scene is true, why one even needs that OTHER OS(Option A) combination? coz same settings are available in Option B i.e. Windows 8 + CSM Support ALWAYS ON

:)

 

Does the Gigabyte GA-Z77X-UD5H Support Windows 10?


My Gigabyte GA-Z77X-UD5H (BIOS F16G) motherboard works fine in Windows 8.1 Pro in UEFI & Secure Boot Mode.


Does this motherboard work in Windows 10 in UEFI & Secure Boot Mode?


It's not on Gigabyte's compatibility list at GIGABYTE Motherboards Ready for Windows 10 but the Windows 10 Compatibility Advisor states my PC is compatible with Windows 10.

 

How to downgrade UEFI to previous Hybrid Bios - Gigabyte

It did when I changed the steps as outlined, also be sure to download the same bios you flash on to a USB drive then run the bios Qflash utility to flash the "dual" bios after you flash in Windows, as the method you posted only flashes the "main" bios.

Though now i have succesfully downgraded from uefi and I couldn't be happier as my stable 24/7 OC became unstable with the uefi bios and Gigabyte offered no way to downgrade to legacy :shadedshu

BTW all the kudos goes to you for the guide I just tweaked it though couldn't have done it without the OP *Toast :toast:

 

gigabyte motherboard and windows 10

Gigabyte 970a-ds3p motherboard

Windows 10 would not install without the betabios (F2J) update on the bios motherboard.

After the update, automatic updates will not install Windows 10 automatically, you must use the MediaCreationTool X64 or X32 depending on your previous OS.

Windows 10 will not boot unless changes are made in the BIOS screen of your Gigabyte MB:

OS type: other

Boot mode select: UEFI and Legacy

Storage Boot Option Control: Legacy First

other PCI device rom: Legacy OpRom

under Peripherals:

onchip sata: Native IDE

Without these changes, Windows 10 boots into a redundant cycle of diagnostic and repair attempts. Make sure your Bios is the F2J before installing Windows 10, and the BIOS changes are made prior to running the MediaCreationTool.