@GrndZero
Sorry, I forgot to address the post to you. Yeah, Windows 10 should have detected it no problem. If you've tried the adapter in other slots with no results, it may be the adapter. I doubt it's the SSD, but it's possible.

@Paulos7 I will take the adapter apart and double check everything.
This is the one I picked up

@GrndZero
It looks like a decent adapter with a nice heatsink, and the reviews were all good. Ideally, you need to try it in another PC that has PCIe slots; or better yet, a native M.2 slot so you can determine if it's the SSD or not. If another PC to test on is not an option, I would reseat the SSD (inspect the contacts, gold fingers, etc) and try again. I'd hate to buy another adapter, only to find out that it's the SSD.

@GrndZero
If it turns out to be the adapter, you might want to consider some German engineering as a replacement . I have the kryoM.2 and the kryoM.2 evo and have had no issues. They're more expensive than others, but definitely top quality.
http://www.performance-pcs.com/aquacompu...e-heatsink.html
http://www.performance-pcs.com/aquacompu...e-heatsink.html

Hi Fernando, thanks for posting up this guide to help everyone out. I'm having a bit of trouble detecting my Samsung 970 Evo, though.

I have an Asus Maximus VI Formula and a Samsung 970 EVO connected via PCIe adapter: https://www.amazon.com/gp/product/B07F9R...0?ie=UTF8&psc=1
I think I followed your instructions pretty clearly but the NVMe is not shown to be connected at all in either the BIOS or in Windows 10. Could my brand new 970 or the adapter be faulty?

Here is the link to the source file: https://www.asus.com/us/Motherboards/MAX.../HelpDesk_BIOS/
Attached is the modded file.

Thank you for looking into this!

First of all, thanks to Fernando for his very comprehensive guide, I had modded BIOSes to change OpROMs in the past, so this was not uncharted territory for me but it still took some effort and I was very thankful for this detailed step-by-step guide. Very well done!

Just in case someone else needs this, I was able to make this work almost flawlessly using a GA-Z77X-UD5H (Rev 1.0) and a WD Black (2018) 500GB WDS500G2X0C, with a pretty basic adaptor (Riitop).

It was a bit tricky since using the second PCI-X port (X8) of the motherboard wouldn't work (sometimes the drive would show up in the UEFI menu, but the EFI-loaded Win installer wouldn't see anything). Also my video card isn't UEFI-compatible so when trying options with exclusive UEFI boot I had to boot on the internal Intel IGFX one temporarily. In the end I plugged the NVME in the third PCI-X port of this mobo (PCIEX4) and it worked without a hitch with the external, non-EFI video card (hence without requiring exclusive UEFI boot), and I was able to install Win 7 booting in EFI (with/without secure boot), and it could see the drive accordingly in the installer.
The SSD shows up as "Generic STORAGE DEVICE 0821" in the UEFI, and activates some options as if it was a USB device, and in some menus (boot override for instance) it shoes up as PATA SS, which doesn't really make sense. You can ignore this and just use the EFI-loaded USB OS Installer to have it working. You shouldn't try booting on the SSD directly from this UEFI without having pre-installed an EFI-compatible OS anyways, as the first post says.
At first I tried with the "official" Gigabyte F16H image since they put native NVME support while updating the MATS (by mistake apparently), but I also got a modded F16J working (which I use at the moment) using the large NVME DXE (the UEFI is 8MB on this mobo, with plenty of space for the large image).

Motherboard: GA-Z77X-UD5H Rev 1.0
NVME SSD: WD Black WDS500G2X0C
UEFI (BIOS): F16J Mod with "NvmExpressDxE_4" module GUID 5BE3BDF4 (F16H without any mods should also work since it contains NVME DXE)
PCI-X Port: #3 (PCIEX4 Slot)
Relevant UEFI Settings:
In "BIOS Features":
- Windows 8 Features: Windows 8
- CSM Support: Always
- Boot Mode Selection: UEFI and Legacy
- Storage Boot Option Control: UEFI First
- Other PCI Device ROM Priority: UEFI OpROM
In the Peripherals view:
- Primary PEG: Auto
- Internal Graphics: Disabled
- Intel (R) Rapid Starte Technology: Disabled (this somehow interfered with the drive recognition).
- USB Storage Devices / Generic STORAGE DEVICE 0821: Hard Disk (not sure if this has any impact).
After the installation, in the "Save & Exit" view, the drive correctly shows up under "Windows Boot Manager (WDS500G2X0C-XXXXXX..." and under "ubuntu (WDS500G2X0C-XXXXX...", but in the "PATA SS:" section it shows as Generic STORAGE DEVICE 0821. Before the installation it was just showing as "Generic STORAGE DEVICE 0821" and there was no "PA SS:" section in that view (even with the right NVME mod).

Warnings:
- Plugging something in the X4 slot reduces the speed of the X16 slot to X8, it should't be an issue for most (recent) video cards, but do verify first.
- This motherboard only supports PCI v3.0 (And the X4 slot only works) if you have an Ivy Bridge CPU.
- As documented in the first post: even if you don't see any indication in your modded UEFI that the drive is recognized/bootable immediately, you have to try to install an OS through a UEFI-booted USB Stick first and see if the installer sees your drive. It clearly won't work if you're in non-UEFI (CSM) mode.
- Not sure this would work with other models of Gigabyte Mobos, maybe I just got lucky, I am not responsible for you bricking your card.

Speed tests are fine:

Dear Fernando!
Decided to install SSD drive SAMSUNG 970 EVO MZ-V7E250BW on the Adapter PCI-e M. 2 NGFF for SSD Bulk on the motherboard P8H77-m PRO as a boot. BIOS does not see SSD. Under W7 sees the SSD fine.
1. Installed THE latest BIOS firmware.
2. Upgraded BIOS by Your technique: inserted module NvmExpressDxe_4.
3. But the upgraded firmware cannot be downloaded. You receive the message: Security verification failed.
Other option.
1. Created bootable flash drive with FPT
2. Kept fully dump the BIOS.
3. Upgraded BIOS by Your technique: inserted module NvmExpressDxe_4.
4. Can't flash the BIOS with FPT and AFUDOS.

Would you be so kind as to suggest and help.

Ссылки на файлы прошивок BIOS
https://yadi.sk/d/cRYMREE7g_7yWg
https://yadi.sk/d/1Uho61c-1iVq_Q
https://yadi.sk/d/_Gc74aWXxG64yA
https://yadi.sk/d/q74cX78oz0fIhg

@Fernando:
Thanks, Dieter!
To be honest, I didn't expect You to respond so quickly. Thanks for the link.
Still, do not find the time to look at the BIOS firmware and determine whether I upgraded them correctly.
https://yadi.sk/d/cRYMREE7g_7yWg
https://yadi.sk/d/1Uho61c-1iVq_Q

https://yadi.sk/d/_Gc74aWXxG64yA
https://yadi.sk/d/q74cX78oz0fIhg
With Respect Valentin

My BIOS was initially already upgraded to version 1603 so I loaded up the previous version (source 1505) onto a USB under the name "M6F.CAP" and used the Asus Flash method.

I held the ROG Connect button down with the USB in first slot until the light starting blinking and when it stopped, I turned on my computer and entered BIOS to confirm that it reverted back to version 1505.

Once it was back to 1505, I deleted the existing M6F file (1505) off the USB and loaded the modded BIOS (1603) onto the USB as M6F.CAP, turned off the computer, and used Asus Flash again.

When I booted the computer and entered BIOS, it was confirmed that the version was now 1603. However, when I check my PCIe slots, only my 1080ti GPU shows as detected and the other two PCI slots were shown as unused. The boot drives only showed my other SSD (840 EVO SATA), DVD drive, and my HDD. Loading up Windows 10 and it also didn't show the 970 detected as a drive. I've attached a couple of pictures. Should I try to get another NVMe to PCIe adapter? Thank you!