Title. I remember reading something about Intel Boot Guard preventing modded BIOSes on these, but that's where my knowledge stops.

I also would be more than happy with having the the overclock lock on the GPU removed!

Let's say it this way... It is possible.
Buzzword: PCHInit - MFG Mode in NVRam

@User32 - Why guess/wonder about Bootgaurd, check and see if it's set at the PCH FPF or not, run MEInfoWin.exe -verbose and look at the bottom of the report, on the left/FPF side, do you see enabled on either Measured or Verified Boot?
I've edited P52 BIOS for user before, so unless there is major difference here you can probably edit this one too. If VB or BG is enabled, then you can only edit certain regions of the BIOS or = brick/lock due to VB/BG

Check BIOS main page and see if ME FW version is shown, if not then download HWINFO64 and on the large window on left side, expand motherboard and find ME area, inside that get the ME Firmware version.
Once you have that, go to this thread and in the section "C" download the matching ME System Tools Package (ie if ME FW version = 10.x get V10 package, if 9.0-9.1 get V9.1 package, if 9.5 or above get V9.5 package etc)
Intel Management Engine: Drivers, Firmware & System Tools

Once downloaded, inside you will find MEInfo folder, and inside that a Windows or Win/Win32 folder. Select that Win folder, hold shift and press right click, choose open command window here (Not power shell).
At the command prompt type the following and show me the end of the report in an image (not text) >> MEInfoWin.exe -verbose

Additionally, inside ME System Tools folder you will find Flash Programming Tool folder, and inside that a Windows or Win/Win32 folder. Select that Win folder, hold shift and press right click, choose open command window here (Not power shell).
At the command prompt type the following command and send me the created file to modify >> FPTw.exe -bios -d biosreg.bin

Right after you do that, try to write back the BIOS Region dump and see if you get any error, if you do show me image of the command entered and the error given >> FPTw.exe -bios -f biosreg.bin
^^ This is important step, don't forget ^^

If you are stuck on Win10 and cannot easily get command prompt, and method I mentioned above does not work for you, here is some links that should help
Or, copy all contents from the Flash Programming Tool \ DOS folder to the root of a USB Bootable disk and do the dump from DOS (FPT.exe -bios -d biosreg.bin)
https://www.windowscentral.com/how-add-c...creators-update
https://www.windowscentral.com/add-open-...menu-windows-10
https://www.laptopmag.com/articles/open-...ator-privileges

Or here is simply registry edit that adds "Open command window here as Administrator" to the right click menu
Double-click to install, reboot after install may be required
http://s000.tinyupload.com/index.php?fil...134606820377175

Boot Guard Status:                                                              Enabled
Boot Guard Verified Boot Policy:                                                Enabled
Boot Guard Measured Boot Policy:                                                Disabled
 
 

That a problem?

Getting error 368 when doing fptw -F biosreg.bin

@User32 - Two things in reply to above post. I don't know on the boot guard, you have to show me image.

Error 368 is easy to get around, but you should not be using FPT in that manner (wrong command to flash, and or dump), please do only and exactly as I instructed.
Be very careful, you can brick your board in a hurry with FPT!!

* Edit - I checked your dump, in regards to menu editing, if VB/BG is burned in at FPF then you cannot edit menu because the files to edit for that are covered by BG
You can however change default settings, stored in NVRAM, either via BIOS flash, grub/Setup_var or Vars dump/edit with H20UVE

And, or, we can test above mentioned MFG/NVRAM edit with RU or edited BIOS region flash via FPT.

* Edit - please send me BIOS images, I need to see root of all main sections you can see in the BIOS.

Currently busy reinstalling one of my Precisions so the P50 has a lower priority rn, will make bios pics later.