I almost sure that u r only getting speeds as PCIe2.0 x4...and by the way wasn't there any other option on that adapter...that's a nice piece of junk, my opinion only. If u set PCIe to Auto or Gen3 it will not matter, 2nd or 3rd PCIex16. I could be wrong...i believe we r talking of a P8Z77-V LX...

@MeatWar:
yeap, so adapter is the issue of speed?

Fernando is right...its only a foto and don't u even think that the adapter uses more than PCIex4.
When IvyBridge/Panter Point came out in the market only with a 3rd gen i5 the PCIe3.0 lanes could be enable, below that with 3rd gen i3 ou 2nd gen processors, by default all was set to PCIe2.0.
So with 3rd gen Core i5 or higher u get 1 x16 or 2 x8 or 1 x8 + 2 x4 PCIe 3.0 8(GT\s) lanes, below that u get PCIe2.0 (5GT\s), even then, there is the specific motherboard model by the manufacturer side.
The real test for u regarding ur adapter, is using a PCIe3.0 enable processor with integrated HD Graphics and testing it on PCIex16_1 and 2, ull get the all picture.
Use AIDA64 or HWInfo...it will report the PCIe interface negotiation.
A side note...SandyBrige-E (X79) doesn't have any problems with cheap adapters (om my side, i've done several test with different adapters).
And that's it...nothing more u can do with 2012 chipset/hardware, remember that what Fernando offers in this topic IS as it IS...

Hello, thanks for the excellent guide. Just wanted to ask about an issue I've been running into after flashing my MSI B75A-G43 board. The modded BIOS was created with MMTool using the latest BIOS (E7758IMS.AA0 - https://download.msi.com/bos_exe/mb/7758vAA.zip) with the NvmExpressDxe_4.ffs file placed near the end of volume 1 after MFLASHDXE but before the pad (zipped file exceeds attachment limit, but modded BIOS was byte-for-byte identical to one @Fernando posted earlier in this thread).
After flashing that BIOS, I was able to boot from my NVMe device, but the system had problems with waking from sleep and rebooting. I created another mod using UEFITool to place NvmExpressDxe_4.ffs at the end of volume 1 (after the pad, and raw files that follow MFLASHDXE), but that bricked my system. I was able to recover by flashing the unmodded BIOS using an external SPI programmer.

Even after restoring the BIOS, I'm seeing issues with sleep/reboot. When booting, there is a delay of about 60 seconds before a message that reads "ME FW update failed, please try again" appears. I see this issue now regardless of BIOS version (modded, unmodded, older BIOS versions) and regardless of how it was flashed (M-Flash utility vs SPI flash). When using SPI flash, I've verified that I can read the memory contents, and they match the BIOS being written. It also happens both with and without the NVMe device's presence. In any case, everything seems to work fine other than that long delay and ME FW issue during boot (which sort of eliminates one of the benefits of NVMe boot). Has anyone seen this happen, or have any ideas on what the issue could be?

EDIT by Fernando: Not working link removed

Most likely Intel ME FW corruption, better check in bios if version of FW is displayed as NA or blank.

Thank you for this great forum.

I bought a Crucial P1 M.2 1TB NVMe drive and connected it to an ASUS P8B75-M using an NVMe PCIe adapter. It was detected by my existing OS and I was able to install Fedora Linux from the bootable install media. However, I cannot boot from it and after a bit of searching reached this forum. As per the instructions I got the latest BIOS from ASUS (version 1701), added the NvmExpressDxe_4.ffs it using the MMTool (v4.50.0.23) and created the new file P8B75.CAP. Could not install this using the ASUS EZ Update due to security failure so extracted it to ROM format using UEFITool. I created a bootable DOS flash drive using unetbootin and flashed the bios using "afudos.exe p8b75.rom /GAN". All 4 steps ran successfully.

However, after a reboot, I still don't see the PATA SS drives in the BOOT section. I can still see the drive connected when booking from another drive. I'm not sure where I have gone wrong. I have attached the stock and the modified BIOS files. Please can someone help?

Hi @Fernando!
I have a Biostar H61MHV V7.0 mobo. Does this trick work on it?

Oh, I've thought it wouldn't work since this mobo doesn't have UEFI. Thank you so much @Fernando!

I tried to follow the procedure with my laptop Lenovo Yoga 710-14IKB but UEFITool gives me the error "Invalid UEFI Volume" when opening the file.

From what I've seen in the BIOS settings it's an InsydeH2O. Is there a way to add NVMe support by modifying the BIOS?

@Fernando:

Thank you very much for the answer, I wanted to change my SSD M.2 SATA 250 GB. for a M.2 NVMe 500 GB. but if it is not relatively easy I will opt for another SSD M.2 SATA.