Hello everyone.
I am trying to flash the BIOS of my H61M-C to support NVME M2.
I downloaded the original CAP BIOS file for my motherboard, version 0511, from the official ASUS website.
I flashed the BIOS through EZ FLASH, and everything went smoothly.
Then I downloaded (AFUWINx64.EXE) the already flashed BIOS file (rom) and saved it on my computer so that I could modify it (paranoia).
I modified my original file using UEFITOOL. I took the driver NvmExpressDxe_5.ffs and also tried NvmExpressDxe_4.ffs.
I inserted the driver into the block where CSMCORE is located (as a reference), at the very end in the free space. I saved the modified rom file and flashed the BIOS (AFUWINx64.EXE with the /GAN key) - successfully.
Then I rebooted. At that moment, my M2 (Samsung 970 EVO PLUS 250 GB) was already in the PCIE slot, and it was visible under WIN 10 64.
BUT, in the BIOS, my M2 is not visible. Either I am possibly doing something wrong or not looking correctly in the BIOS for my M2.
I am attaching all the files mentioned above.