Thanks a lot!!

Flashing went smooth.
In (UEFI) BIOS, the Disk shows up as "PATA SS". I can select it as boot drive. Jippeee! ;)

However, I can't access the drive.
E.g. if I boot from Windows-Install-DVD, the NVMe shows up but it wont allow me to install to the drive.
Error code 0x80300002.

I'll research some.

After the first miss when I wasnt following your guide I made double-sure I would do things right this time :D.

I disabled FastBoot. I disabled Secure-Boot as much as I can.
Regarding SecureBoot: My BIOS lets me choose "Type of OS", where I can choose "Windows-UEFI" or "Other OS".
Is it possible that i have older keys still loaded?

OK tried all that.
Bottom line: doesn't work :) .

The main issue is: the thing doesn't survive a reboot.
When I switch on the PC with the NVMe installed, it sees a PATA SS: and an UEFI Windows Boot Manager that I could boot from.

After a reset or reboot, the device is gone.
Doesnt show up neither in BIOS nor in Windows device manager.

The same SSD (WD_Black SN750) plus the adapter (Silverstone ECM21) work flawlessly in a newer, different PC (the one from my son ;) ).
That's how I installed Windows to the device.

If I try to install Windows on my P9X79WS mainboard to this after first boot, the setup comes so far as to copy 17% of the files of Windows from the install DVD (via UEFI).
The 17% are reproducible.

Any ideas?

Fast boot is OFF
SecureBoot is OFF, I deleted all previous keys stored on the board.
CSM is set to "UEFI first"
Booting from PCI/PCI-e is ste to "UEFI ONLY"

Thanks,
McT

Do not use CSM Enable to UEFI first, only CSM disable as it goes to full UEFI mode only.
The option for PCIe UEFI device first is useful when we have a boot device with embedded ROM.
And follow Fernando's advice... dont clone OS installations, always a clean install, avoid optical install media, use USB2.0.

OK will try again :)

Can't fully disable CSM - without CSM, the PC won't boot as it complains about an incompatible VGA Card :D .
I will set the CSM to boot "UEFI only".

So far I tried with enable SATA but booted off an DVD in UEFI mode.
That install always stops at 17%.

Geeze, I miss the old Amiga days - add a device to a custom ROM and that's it :) .

Just want to thank you, I followed the instructions and everything is working perfectly.

I installed Win10pro off a USB flash drive that was prepped via Microsoft site.

Asus Maximus IV Extreme, Ivy bridge, core i7 3770k, Samsung Evo 970+ 1tb.

Some updates and I would kindly ask for some help here ...

So I started from scratch.
I assume the fact that last time I did see a "Windows Boot Manager" was due to the fact that I did install the drive in a different PC.
After accessing it during an attempt ot install that seemed to be wiped.
From thereon, I can't access the drive any more, its doesn't show up anywhere.

So I did start from scratch.
- wrote the bios file again to mainboard.
- I used the one that was verified by fernando to include the necessary file at the correct position
- I dumped it afterwards as a rom with the AFUWINGUI.EXE tool.
- find the respective new rom here: mega.nz -> /file/i3oRyaTS#eG1FDuVwUEcAhk6OevsJQDWIpAJgbI4ctGgT8vlXhsg
- I confirmed the driver NvmExpressDxe_4 is in there (different volume-counting than the MMTool, though)
- After rewriting, all BIOS settings were erased, as they should be.
- the following bios settings are used:
- Secure boot: OFF, all keys deleted. *Other* OS selected, NOT "Windows UEFI"
- Fast boot: OFF
- CSM (compatibility manager): can't be set to "off" as the VGA card isnt comnpatible. i chose everywhere to only include UEFI items.

The drive does not show up anywhere.

Any ideas?

It is correct, it will not be displayed now, it will be displayed in boot manager and/or PATA SS, after installation not before as this is a workaround to old motherboards.

Disconnect all other storage/boot devices, leave only PCIe NVMe device.

Now i do insist with u to use a USB windows installer and proceed with CSM UEFI enable
or remove ur GPU and use ur processor iGPU if possible and CSM fully disable.

By bios boot selection, select boot from UEFI (Your drive USB name), as it can appear as UEFI USB and just USB (This one means legacy boot from USB), this depends on the creation tool used
to create the installer, by doing this u know that ur booting an UEFI installer of windows.

Finish installation and ur system will reboot now from NVMe even with out change CSM...latter if u get an UEFI GPU on it, change this to disable.

...What model of CPU do u own and what windows ur trying to install?

@MeatWar
Can't remove GPU, it is a XEON processor.
No iGPU.
It is about a Win10 installation.
I understand that the issue here is the non-uefi compliant AMD HD7970.

I started from scratch to ensure that any leftovers from the previous installation in the different PC was removed.

I'll do one more round with SATA disabled :D .

Zitat von McTrinsic im Beitrag #5650

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- Secure boot: OFF, all keys deleted. *Other* OS selected, NOT "Windows UEFI"
- Fast boot: OFF

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