Hi,
I successfully added NVME support using the “NvmExpressDxe_Small” module as well as added Resizable BAR with 4G Decode enabled.
I added the modules using Fernando’s guide for adding the NVME module using UEFITool.
4G Decode was enabled by changing the parameter to USER for the PCI Subsystem menu using AMIBCP 4.55 to edit.
The modifications were performed on a stock ASUS bios. I forgot to update the microcode and bios drivers before compiling and flashing but that doesn’t affect functionality. It should be noted that this file is in .rom form so you will have to recompile it into a .CAP if you are trying to flash using the ASUS AI Suite.
I used an EZP2023+ to flash and tested using spare chips since the AI Suite never seemed to work correctly.
The link to the file is below:
Use it at your own risk.
I highly recommend having a flasher on hand. Since you will get a POST code error if you go beyond the 2048MB BAR size on Ivy Bridge. It should be noted that considering the 2048MB allocation limit, this applies to the entire system. So if you have two cards for example you can only set the BAR to 1024MB. I can confirm this since I have graphics cards in my system and it would not boot with two cards in while the BAR was set to 2048MB.
