Hello, I want to mod the BIOS to unlock the hidden “Advanced Settings” menu. I’ve tried checking with Universal Bios Backup and UEFITool, and I found the “Advanced Settings” menu, which includes options like OC and RAM overclocking, but they are disabled by default. I attempted to change the value 0x443 from 0x0 to 0x1 via grub, but the menu still doesn’t appear in the BIOS.
Here is the link to the BIOS version I’m using.
https://www.dell.com/support/home/en-us/drivers/driversdetails?driverid=r92tf&oscode=wt64a&productcode=precision-17-7750-laptop
Can you dump your full bios? You will probably need to use a CH341A programmer to physically dump your full Dell bios. Maybe you’ve already done that, but the size is too big to post here, even compressed with a zip tool?
If you can or have pulled your full bios, you might want to try using the UEFI-Editor. I’ve only messed around with it, but it might be worth a look.
The attached are, I think, the 4 files you need to run the on-line UEFI-Editor program that I extracted from the Dell bios region (after running the latest Dell bios update through BIOSUtilities to extract all bios update components).
UEFI Editor Files.zip (927.7 KB)
I think. Check my work with your own UEFITool extractions. Good luck!
I just ran into an issue where I FPT flashed a bad bios on a bricked board, and it posted anyway. I couldn’t understand how that happened. The only thing I could think of is that there was enough in that bad bios to draw from a backup on the OS SSD.
From everything I’ve read, you can’t modify just the bois section (from the Dell update) and successfully flash it. You’ve got to flash the full bios. So the only thing I can think of is that your bios “recovered” from a bad flash.
I looked more closely at the results of the UEFI-Editor run with your modified bios. Under 0x800A Maintenance - BIOS Recovery, it doesn’t look like the values changed, so I’m assuming that’s what happened - and what happened in my situation also.
You could change that to not recover, but I’m pretty sure you’ll brick your computer.
From everything I’ve read, you have to pull a full bios, modify the full bios, and then flash. My desktop has a service mode pin that should allow for a full FPT bios dump and modified bios flash. I’m guessing that your laptop does not, so you’ll have to dump and flash with a CH341A programmer.
Edit: I’ve had a tough time FPT flashing a full bios. Having no service mode pin will make flashing a Dell even harder.
