Dell Precision 5820

BIOS/UEFI Modding BIOS Modding Requests
1

Hello. I am trying to extract the bios files from this bios: https://dl.dell.com/FOLDER11491866M/1/M33X_2.36.0.exe .

I am following this tutorial: Enabling hidden 4G decoding · xCuri0/ReBarUEFI Wiki · GitHub as i am trying to enable rebar on the machine and it required a bios bin file. After some poking around i found GitHub - platomav/BIOSUtilities: Various BIOS Utilities for Modding/Research and am able to get bin files (produces 2 folders: 3 CombineBiosName2 v99.1.45 and 2 CombineBiosName2 v99.1.45). Within those folders there are a number of bin files.

I choose 3 CombineBiosName2 v99.1.45 – 1 System BIOS [V0 AMI] v2.36.0.bin or 2 CombineBiosName2 v99.1.45 – 1 System BIOS [V0 AMI] v2.36.0.bin and using UEFITool do a search for “4G Decod” and it finds entries and when i select extract body it seems to extract a file, but when i run it against ifrextractor (.\ifrextractor.exe .\4GDecodBody.bin) it doesnt produce anything. This is all over my head but was hoping to get some help.

2

Why such trouble if the system will deny (most probably…) any flash mod due to security issues…
Work on a FPT dump from the current system bios, only need the bios_region for such mod.
After all… this is the first action that a user should do before engaging in bios mod…BACKUPS.

3

Hey @MeatWar thanks for the reply. Honestly i have no idea what any of this stuff is. How do i go about creating an FPT dump of my bios? Im currently running unraid on the box in question so if there is a shell command i can run to get that, that’d be great. Also if you have any additional documentation on how to enable rebar on older hardware that’d be super helpful. Im a noob at this and just want that enabled so i can be ready when unraid’s kernel adds support for Intel Arc cards.

4

As this is not easy teaching, besides quoting the tool cmds, i would suggest to do some forum reading from the Intel MEI section.
The Intel FPT tool uses the system MEI to perform several operations of reading and writing… when possible, regarding the FD (Flash Descriptor) status.

Intel (Converged Security) Management Engine: Drivers, Firmware and Tools (2-15) - Special Topics / Intel Management Engine - Win-Raid Forum (level1techs.com)

ME Analyzer: Intel Engine Firmware Analysis Tool Discussion - Special Topics / Intel Management Engine - Win-Raid Forum (level1techs.com)

[Guide] Unlock Intel Flash Descriptor Read/Write Access Permissions for SPI Servicing - Special Topics / Intel Management Engine - Win-Raid Forum (level1techs.com)

A note… careful with this tool as it performs the cmds given without verifying the data content, the human error here is the culprit.
Good luck.

5

Have downloaded the file (ReBar.exe) and enable it since you’ve done the modding,if you have no idea with that send the .bin file (if you’re willing to share it), I will modify and give u the dump file