Disabling CSM Support Causes Boot Failure

[Kyouma]

A little background:
 - I have a pre-built PC (Gigabyte AX370 motherboard) that I am trying to add an SSD with windows on it to speed up boot times and other operations.
 - Secure boot denies any attempt to boot from USB or any device that isn't the HDD the PC came with.

 - I need to disable CSM support to disable secure boot. 

 

Once I disable CSM the computer posts, but does not display BIOS or seem to boot into the specified USB with windows installer on it. Clearing CMOS does bring the BIOS display back, but any attempt to disabling secure boot leads to the same result. Anyone know how I can disable secure boot and install windows on the SSD I want?

 

Edit: The GPU seems to be incompatible with UEFI without CSM support. The problem was misdiagnosed (because I can boot from a linux USB) and I will make a new forum for it.

Edited February 18, 2021 by Kyouma
Problem Update

[Kyouma]

I have an RX 580 4gb, I believe it should. I will double check.

[xAcid9]

14 minutes ago, Kyouma said:

- I need to disable CSM support to disable secure boot. 

If I recall correctly, you just need to change OS Type to Other OS to disable Secure Boot. 

 

 

[Kyouma]

20 minutes ago, xAcid9 said:

If I recall correctly, you just need to change OS Type to Other OS to disable Secure Boot. 

 

 

Gigabyte or my version of BIOS does not have the OS Type option. The following is what my screen has: