Bios Mods -The Best BIOS Update and Modification Source

I tried it again. The setting gets reset on boot

Try
setup_var 0xA3
setup_var 0xA3 0x01
setup_var 0xA3
What are results?

0x00
0x01
0x01

Then reboot and go back in to EFI
0x00

Try
setup_var 0x82
setup_var 0x82 0x00
setup_var 0x82
What are results?
Reboot
setup_var 0x82
setup_var 0x82 0x01
setup_var 0x82
What are results?

0x01
0x00
0x00
reboot
0x01
0x01
0x01

Can you disable VT-x in BIOS and try that again.

after disabling vt-x in bios:
setup_var 0x82 returns 0x00
I set it to 0x01 and rebooted to BIOS
BIOS says vt-x is disabled

edit: the setup_var options are definitely overridden on each boot

So setup_var can't change setting in BIOS.
So I can't help you without a hardware programmer (CH341A) and SOP16 flash clip to DIP8 .

these 2 items ok?
https://www.ebay.com/itm/232143318171
https://www.ebay.com/itm/332156943251

OK.