Samsung Chronos NP770 NP870 disable discrte GPU

[faeterov]

Hi everybody, I would like to request some help for some old laptops I have at work.
This Samsung Chronos laptops (Core i 3rd gen) are excellent, but unfortunately their dedicated Radeon 8870m GPUs are starting to give me more problems with current drivers, and the way microsoft pushes updates.

Many years ago I managed to mod a bios to disable the Radeon GPU an only let the iGPU run, but I cant seem to fin it, and also Im a little out of training in using AMIBCP to mod said BIOS.

I was wondering if some of you could help me modding the original BIOS, or at least helping me remember where was that option in the menu. Im attaching some pictures of places that ring a bell in my memory about disabling the dGPU.


https://mega.nz/file/1UkEWBKT#MzpfDHrvOd...5v7vWiz6iA

[faeterov]

Just wanted to share that I found the other laptop that I allready had modded its BIOS, it a NP770z5e, BIOS revision P07ABU, not the same one that I uploaded originally, but I'll try to remember what was originally changed.
https://mega.nz/file/wNFxjIhD#S1sCd39GjS...FmJvNdNN-s

Also Im posting a comparison between the original of that laptop, and this new one.

[faeterov]

This is the final BIOS that I made, that has the dedicated AMD GPU disabled.The procedure was to dissable in the main menu the dgpu, by selecting de igpu and opting out of "SG".

https://mega.nz/file/8A8ySB4S#wHIgM0NLNW...Jjz91QFsBw

[zerooo]

Just wanted to share that I found the other laptop that I allready had modded its BIOS, it a NP770z5e, BIOS revision P07ABU, not the same one that I uploaded originally, but I'll try to remember what was originally changed.
https://mega.nz/file/wNFxjIhD#S1sCd39GjS...FmJvNdNN-s

Also Im posting a comparison between the original of that laptop, and this new one.

Hi, I have the same samsung model/bios and my dGPU has died so this laptop cannot install/use Windows anymore (getting freezes and need to reset), although with disabled amd drivers I can use it for linux `modprobe.blacklist=radeon,amdgpu` I would prefer cleaner solution to disable dGPU in BIOS for use in all OSes.

Can I flash your BIOS and do I need a CH341A USB programmer or I can do it via software (AMI_AFUWINx64_4.48) or similar?

My laptop information:

Code:

System Manufacturer SAMSUNG ELECTRONICS CO., LTD.
System Model 770Z5E/780Z5E
System Type x64-based PC
System SKU SAMSUNG SENS Series
Processor Intel(R) Core(TM) i7-3635QM CPU @ 2.40GHz, 2401 Mhz, 4 Core(s), 8 Logical Processor(s)
BIOS Version/Date American Megatrends Inc. P07ABU.147.140421.SH, 2014-04-21
SMBIOS Version 2.7 Embedded Controller Version 255.255
BIOS Mode UEFI
BaseBoard Manufacturer SAMSUNG ELECTRONICS CO., LTD.
BaseBoard Product NP770Z5E-S01EE
BaseBoard Version SEC_SW_REVISION_1234567890ABCD

[faeterov]

Bios model is the same = It should work.
That being said, if you want to mod the BIOS yourself I posted the procedure.

[zerooo]

I'm still a bit lost new to modding bios. Could you please answer the following:

1. What do you use to get the original BIOS to mod it? 
   
2. Do I use the AMIBCP-4.53.0050 software as posted in the screenshots? I'm not sure I can see these options there.
   

   The procedure was to disable in the main menu the dgpu, by selecting de igpu and opting out of "SG".

3. How do I flash it back once it's modified?
   

Thanks!

[faeterov]

I followed this guide

https://www.bios-mods.com/forum/Thread-G...EFI-Aptio4

Yes, I used  AMIBCP-4.53 like the screenshot shows.

[zerooo]

These are the steps I followed when modifying my saved bios on AMIBCP 4.53 (I followed this guide exactly):

To ensure your display works seamlessly on integrated graphics, double-check that these three key settings are configured together in your modified ROM before saving:

Primary Display Select: Set to IGFX (forces the system to initialize Intel graphics upon boot).
Internal Graphics: Set to Enabled (keeps the Intel GPU permanently active instead of switching or turning off).
Enable PEG: Set to Disabled (turns off the PCIe lane connected to the dead AMD chip).

With this combination, your laptop screen will run entirely off the Intel CPU's graphics core, completely bypassing the failed AMD hardware. Which did not work correctly on previous modifications posted in this thread.

Attached the bios I modified to this post tested and working fine.