Windows 10: How to change Legacy to UEFI without reinstalling Windows 10

Some new generation motherboards for PCs and Laptops bring in support for both UEFI or Unified Extensible Firmware Interface as well as BIOS or Basic Input Output System. The main advantage of UEFI over the traditional BIOS is the fact that UEFI supports a hard drive with [...]

This post How to change Legacy to UEFI without reinstalling Windows 10 is from TheWindowsClub.com.

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Change from Legacy to UEFI for Windows 10

Hey so a while ago I messed up with my previous windows 8.1 and I had to change settings to Legacy, now that I upgraded to windows 10 could I reinstall windows 10 with UEFI in a bootable device so I can get windows 10 working again with UEFI? If so how
could I? I'm not really a computer expert, thanks.

 

Legacy to UEFI

I'm debating moving to UEFI form my now legacy BIOS (Award Software Int.) the mother board is a GA-Z68XP-UD3 rev1.0 on the the following link it shows a UEFI BIOS U1J )UEFI BIOS)

GA-Z68XP-UD3 (rev. 1.0) | Motherboard - GIGABYTE Global

Currently I'm running the legacy F10 BIOS. Does installing the UEFI BIOS automatically take care of everything to get to the UEFI BIOS? Installing the UEFI BIOS following the instructions using the Q-flash method GIGABYTE How to Reflash Motherboard BIOS

What's steps do I take and in what order?

Much appreciated

 

Quick UEFI/Legacy question

I have had Hawaii cards and Fiji cards with UEFI roms, used 1 at a time on an Asus P5K Premium motherboard LGA 775 with Q6600 without an issue. AMD ROMs are Hybrid ROMs ie have a legacy section with UEFI module, so you won't have an issue with card which has UEFI ROM on legacy system. The legacy sytem will just ignore the UEFI module in vbios.

To make Windows show UEFI as bios mode you need your Z97 Pro Gamer in "Pure UEFI" mode (ie CSM = OFF). Windows IIRC only changes between legacy / UEFI on install, so even if you change to CSM=Off it may not show UEFI bios mode in Windows system info tool. I have not had 2 GPUs in a system at one time, even if I had them, I thought my PSU was not up to the job, so can not comment if only the primary display card requires UEFI module and it is irrelevant if secondary GPU does not.

If you get black screen/issue after setting CSM off then remove the card with legacy ROM, if mobo boots then you'll know you need to update the ROM on that card.