[Request] Unlock the BIOS HP ProDesk 400 G1 MT ms-7860

[Methanoid]

@rupik - did you test his BIOS and can you confirm it unlocks the other menus? Would love some screenshots of the Advanced and Chipset menus that should be present (see this video https://www.youtube.com/watch?v=bq-Sc5U6MYM) 

I want to know if it unlocks CPU multiplier change on K series CPUs (even if voltage is fixed).  I am planning to buy this board/system

[krechbk]

Unlock the BIOS HP ProDesk 400 G1 MT please tring to get nvme to boot

[manu69xyz]

Unlock the BIOS HP ProDesk 400 G1 MT please tring to get nvme to boot

I managed to add NVMe support to my HP ProDesk 400 G1 MT ms-7860. I followed these steps exactly.
1) Update the BIOS to the latest version available from HP, L02 v.02.56 of 04/24/2019
2) Identify and read the name of the BIOS chip (it will be used for the flash)
3) Using the CH341A programmer + the SOIC8 SOP8 Test Clip (€4 on AliExpress), make 3 backups of the BIOS
4) To make the backup, you need to remove the CMOS battery and the CPU. Once the clip is securely fastened, you need to power the motherboard by turning on the power supply by connecting the green cable and a black ground with a paper clip and then connect the CH341A to the USB port of a laptop to be used for the flash.
5) For the flash, I used the AsProgrammer_2.1.2 program which also contains the drivers for the CH341A (to be installed separately) CH34XPAR.EXE
6) If you have connected everything correctly, pressing the icon with the question mark will tell you the type of chip.
7) At this point, from the From the list, select the name of the previously read chip.
8) Use igorware-hasher-x64 to verify that the three backups are identical.
9) At this point, you must first erase the chip.
10) Then, load the BIOS modified with UEFITool_0.28.0 and, making sure to first select the live verification option in the options, you can now finally flash the drive for writing.
11) Optionally, you can perform a post-flash verification.
12) With an NVMe/PCIE adapter (about €2 on Alixpress), you will get boot and about 1700MB/s read speed.

Attached are a BIOS modified with NvmExpressDxe_Small and one modified with NvmExpressDxe_5. To modify with UEFITool_0.28.0, once the latest DXE driver (usually CspLibDxe) has been identified, the new NVMe driver should be inserted immediately after Freeform and before Free Space.

The same MT ms-7860 board is used for both the HP ProDesk 400 G1 MT and the HP ProDesk 400 G2 MT. I prepared the NVMe BIOS for both versions. A wrong BIOS causes the errors already mentioned: 2234-HECI error during initialization. 921-Front USB 1 Not Connected. 512-Rear Chassis fan not detected.