@qus1
@mrplamp

Ive been following this subject and went reviewing that Z68 thread...
I dont want to be negative on this and i do understand both ur cases upon ur needs, in theory... u can say that the only change on both chipsets Z68/Z77 is the CPU PCIex2.0/3.0 but
indeed it shouldn't affect the PCH PCIe 2.0 so u can say that this GA-Z77M-D3H suffers from same principle as the Z68...now u can observe by block diagram of the GA-Z77 the "Intel Standard design" that PCIe CPU is independent of PCIe PCH but...
has Gigabyte done it with a few abbreviations" to this...for their AMD Crossfire support?
The Z68 pch PCIe settings was indeed set to x1 on some models, the efforts between Gloobox and Lost_N_Bios were successful, but mrplamp board has fewer PCIe slots and its suppose to support Crossfire...
Gloobox issue was different, the 2 PCIe x16 slots to CPU was doing the rigth split (PCIe2.0 2x8) and we wanted to use the 2nd PCIEx16 slot...not a PCH slot, so in final he got the GPU x8 and the NVMe x4 as intended.
mrplamp wants to use a PCH slot but Gigabyte uses also that slot for Crossfire...this is the dilema as his got fewer slots implemented in the board design

Now back to mrplamp issue, by editing the PCIe from ME region bootstraps, u should check before what devices/ports will be disable (By block diagram u can see LAN PHY/PCIe x1 slot) but be aware the critical here that break the system if affected,
is the PCI bridge. Even so if it works as did for qus1...still that issue u refereed to AMD crossfire.
Now again...i didnt saw anything in ME FW image or bios visible/hidden settings that by AUTO consideres the occupied PCI2.0 x4 with a PCIe card, to be a GPU in Crossfire mode.

To my final statement, there is the option to force PCIe x16 slots to GEN3 instead of AUTO...could this mislead and trick the system...probably not. Does another M.2 card adapter give a different signal to slot and the system sees him a a standard PCIe card and not GPU...
This setting can be deeply encoded in the firmware of Gigabyte and we cannot see him... so mrplamp try the PCH strap edit in the FW image, if doesn't work as ur needs...we can blame Gigabyte design in this mATX board...or not as it was built upon their desire.

Ill stop following this issue now as i do not have anything new to add or a board of same model to explore deeper.

Hi @MeatWar i flashed his x4 bios but then the pc refused to start until i used backup bios , honestly bro i was so scared i thought 100% the pc was gone and backup bios wotnt even load, the cpu fan wasnt even working??

The F15a backup bios is really bad causing alot of time to get it to work, im going to probably go back to f13. il redelete the dxe and reinsert nvme.
Also the nvme module will only work when i select whql otherwise it will go into an hour long struggle to even boot with ram changes being necessary.

hi @qus1 will have a read this weekend. just hope i can unlock again to use fptw64.exe flash to descriptor region, is it even necessary if i have bios and me access?

Thank you for your heroism Master @MeatWar .

Ill pvt you with my success however long it may take me to level up! i have another m.2 adaptor ill try this weekend.

I'll find the time to contribute all my findings an effort once concluded, im buying the m.2 to sata as soon as its on special and putting this to bed also.

<3 all the best bro

now i can add links
for edit bios in fit u can check this NVMe module integration to Gigabyte Z68P-DS3 legacy award bios help need. (6)
about what did u need to edit in fit u can read here NVMe module integration to Gigabyte Z68P-DS3 legacy award bios help need. (5)
for fast repair bios will be good to have ch341a+sop8 buy in aliexpress
i use default bios flash, next step update me firmware, and next step flash bios mods its always working for z68

@qus1,

Think i fnially found the reason why.

These lunatics at gigabyte couldnt even code the correct bus or device into their cross fire attempt . The two other PEG's which ware linked to the GPU and its lanes are not even located on my pc, those decvices dont even exist.

Hi @qus1

bro, ever since locking my master region my sound has stopped working.

I thought it was because i only added the vscc table which was applicable to my spi chip but then i reverted the bios to the normal one and my sound still refuses to work!!

I reinstalled amd drivers and standard drivers but still :'( wtf! i can't believe it man, feels like i need to do a windows 10 reset or remove my gpu and ram and retry adding them- perhaps the i/o hub is f#$king up the dmi lanes for sound??? i dont know.

Device manager says it is working normally? so im not sure, im thinking it is the gpu not sitting properly or something because i reverted all things back to correct driver? im not sure but i wasted another two weekends trying to fix this, man i suck so bad.