Adding NVME boot support to Asrock Z68 Pro3

 This is possible and it worked for me. However, use at your own risk: Flashing BIOS is risky.

  The main idea is from this post.

Notes:

1. Original BIOS version was 2.30  . This had padded sections so I couldn't use UEFITool. MMtool worked fine to insert NVME support. 
2. Older BIOSes had no space to insert even compressed version of NVME support
3. This worked for me on an Intel drive
   
4. NvmExpressDxe_4.ffs was not sufficient to add boot support.
5. I extracted the 3 NVME support files from Asrock Z97 Pro3 and inserted them into 2.30 instead of NvmExpressDxe_4.ffs . This worked and both Windows and Linux can boot from NVME. 

As an initial caution, I disconnected all other drives from the motherboard. UEFI defaults. I'll add other components one by one.