x79 already have 4G decoding in bios doesnt work with rebar

[protocold]

Hi everyone,

I’m using an X79‑3.2s1 motherboard. The BIOS already has “Above 4G Decoding” enabled, and it boots fine with a P40 GPU under Linux.

I added the DXE patch, flashed the BIOS, and enabled ReBAR by running ReBarState and setting it to 32. Despite this, ReBAR still doesn’t appear to work.

Since the board already includes Above 4G Decoding, I assumed the “Extend MMIOH limit” patch in patches.txt wasn’t necessary. However, when I uncomment that line the patch applies correctly (a 10‑byte change).

What am I missing? Has anyone else successfully got ReBAR working on this board? Any guidance would be appreciated.

[Koekieezz]

Werent pascal wont work with rebar at all due to driver level restrictions?

[protocold]

good insight. I read from this link that someone got rebar to work with their P40 on their dell: https://www.reddit.com/r/LocalLLaMA/comments/1epprn4/t7920_will_not_post_with_dual_p40s/

[Koekieezz]

good insight. I read from this link that someone got rebar to work with their P40 on their dell: https://www.reddit.com/r/LocalLLaMA/comments/1epprn4/t7920_will_not_post_with_dual_p40s/

That user used normal rebaruefi, do you have your clean bios dump/stock bios by any chance?

[xCuri0]

So did the patch make any difference ?