Mainly just need to know the gist to expose DVMT. I have a full.rom, a CH341A and time to burn.
I was unable to find it (because Lenovo?) it only contained an update, not a complete BIOS. However I have a .rom dump from a CH341A.
I understand people here are quite helpful with simply patching the BIOS, but I’m more interested in how to DYI if you can provide information to point me in a direction.
Please link me to Lenovo BIOS download page, I only need to look at the BIOS region anyway. And yes, I noticed you wanted info/to do mod yourself, that’s why I didn’t ask for your dumped BIOS (yet)
If it’s an easy edit I will tell you how to do it, if it’s Insyde BIOS though I may not be able to tell you how to unlock the BIOS (I hate Insyde, but sometimes can do it)
If the BIOS setting you want are in an already visible to you section, just hidden, that would be much easier edit and I would be able to tell you how to reveal those without issue
Thanks for the response. I’m not quite sure if this is the exact BIOS, given Lenovo’s naming scheme with these models but this is where I obtained the NVRAM/ExtraVars to repair my BIOS when I previously corrupted it.
https://pcsupport.lenovo.com/us/en/produ…nloads/ds101359
a9cn61ww.exe (Broadwell)
I have used UEFITool to extract GUID: CFEF94C4-4167-466A-8893-8779459DFA86 (PlatformHiiAdvancedDxe) and then used IFR Extractor on that dump.
Is this where I need to modify?
0x4CFCD
Security: Permissions: [85B75607-F7CE-471E-B7E4-2AEA5F7232EE]
{60 92 07 56 B7 85 CE F7 1E 47 B7 E4 2A EA 5F 72 32 EE}
…
One Of: Internal Graphics, VarStoreInfo (VarOffset/VarName)
friendly bump
@REKTIMU2 - Sorry for delayed reply!!
If you just want to change default applied settings, it would be in PlatformHiiAdvancedDxe as you mentioned, also some in here >> 76016A54-9959-495D-BB3E-BA35E25A51CB_SystemSetupMainDxe
Or, within NVRAM (Setup or Custom or both), some BIOS use setup for applies defaults and some rely on what’s in NVRAM only. Only you can find out which this system uses by changing one area at a time and then test if changed defaults apply or not.
DVMT settings are in “Setup” NVRAM - 4DFBBAAB-1392-4FDE-ABB8-C41CC5AD7D5D
XMP settings are in “SaPpiSetupVar” NVRAM - 7DA81437-866B-4143-8E08-A25C6EF0FA5B
If you edit stuff in any NVRAM module, be sure you are editing settings locations of extracted “Body” of each module only, otherwise your locations will be off due to the header for each
Bump