Try different RAM, Coreboot for some reason is VERY picky with RAM on these machines. My best combo ended up being one stick of PC3-8500S and one of PC3-10600S, also could try one module only.
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MBP 1,1-10,2 Permanently Disable 2011 15"/17" MacBook Pro Dedicated GPU - gMux IC Bypass
- Thread starter dosdude1
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And what should I see for the first boot? Coreboot have BIOS config? If yes, how can I go in?
I tryed all combinations with G-Skill 8 gb, Kingston 4 Ggb and Hynix 4 gb, unfortunately all 12800 or 12800s. No dice!! I'll see what I can try more next days. If anybody have suggestions, please. In all situations just with 1 ram bank I have a bit of light around the frame, but nothing more.
Oh if you have backlight, it is POSTing, but there's a video issue. I'll see if I can fix that, as that's an issue with the Coreboot build.
Hehheheh! Evrika! I saw the splash. I was inside the settings. Very unfamiliar. Tried to boot Ventura, but reboot. Please give me the OC config, or some hints. Thanx man!
It boots with just the upper memory slot!
After playing around with RAM's I have, I can confirm that both slots are working. I have installed now on my MBP8,2 bootcore, 12 GB RAM. After I'll have the OS's installed, I'll check the working memory chipset and I'll report.
Thank you @dosdude1!
For sure I'll have more questions in the near future.
Update: All RAM combinations give 666 MHz, single RAM (1600 MHz) give 800 MHz. I can reach Ventura desktop, just remotely. The display is always black. Also I can't get into windows installer. The process stall at the ring going around (the ring don't stop, but doesn't go to the installer screen).
In Ventura all tree sound appear in ioreg, but no sound from speakers. No way to make USB working (the USB tree is not in ioreg). Firewire is present but I don't tried. Thunderbolt also present but an ethernet adapter doesn't work.
I'm waiting for your EFI to see if it is my fault with the black screen issue or is cose of coreboot.
Looking forward for your reply!
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Hi everybody, i'm new here and i'm looking for some help trying to disable the dGPU of my macbook pro 15 inch 2011 mother board 820-2565-A. i've got an error when trying to read the gmux ic from my lattice "error when verify the ID" or something like this.
i've read that i should need to remove the L2406 from the motherboard in order to get it work but when i do so the macbook not start fully it stay on black screen with the fans at full speed.When i try with the L2406 on the mother board the lattice led came green but i can't read anything from the chip..
Someone have an idea ?
Many thanks ! ( sorry for my english ^^)
i've read that i should need to remove the L2406 from the motherboard in order to get it work but when i do so the macbook not start fully it stay on black screen with the fans at full speed.When i try with the L2406 on the mother board the lattice led came green but i can't read anything from the chip..
Someone have an idea ?
Many thanks ! ( sorry for my english ^^)
Thanks for your coreboot image, and also for the patch on failing dgpu, it helped me a lot.
Are you gonna share source code of your coreboot build ? I'd like to try to build it myself with a tianocore + some uefi module I made, It would be the first computer with my own efi program loaded directly inside the bios ^^
Hi, @dosdude1
Can you, please, share you coreboot sources from latest message?
I successfully build a coreboot, based on MacBookPro 8.1 sources, changing the backlight registers, and adding video BIOS from Lenovo T420. Windows now starts and working ok (except hibernation), but quite a few ACPI devices (light sensor/etc) are not detected. They work in your build.
Can you, please, share you coreboot sources from latest message?
I successfully build a coreboot, based on MacBookPro 8.1 sources, changing the backlight registers, and adding video BIOS from Lenovo T420. Windows now starts and working ok (except hibernation), but quite a few ACPI devices (light sensor/etc) are not detected. They work in your build.
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I've installed Windows 11 on my still fully working MacBookPro8.3, running in UEFI mode via OCLP. I've enabled the "pass through iGPU to Windows" option in OC. While both the dGPU and iGPU now are visible in the device manager, installing drivers triggers a code 43 error for the dGPU, and the iGPU suddenly seems to be directing output to a non-existent secondary monitor. As a result, the internal monitor relies on the non-inizialized dGPU with basic display driver, and the iGPU "second monitor" just shows a black screen when switched to.
Is there a way to utilize the iGPU in Windows on the MacBookPro8.3?
Is there a way to utilize the iGPU in Windows on the MacBookPro8.3?
Here is an example of the settings. Instead of the file shown in the screenshot, you can use the video BIOS from Lenovo T420, found in articles about coreboot.
And keep in mind, I have physically removed the GMUX chip and the backlight is controlled through the PCH, as in this article
GitHub - ayilm1/gMUXBypass: Bypass graphics multiplexer on 820-2914 and 820-2915
Bypass graphics multiplexer on 820-2914 and 820-2915 - ayilm1/gMUXBypass
github.com
P.S. I have a MacBook Pro 15 2011 (MBP8,2)
Attachments
Yep, I’ll get that together for you. Be warned it’s a bit of a mess, and needs a lot of clean up, but works.
Hi! I'm having the same issues as you. The pc boots on Coreboot only when there is a single stick of RAM inserted in the upper slot; also, I can't manage to reach the windows installer, I'm stuck at the circle going round. Same story when trying to boot a windows installation already made on another computer. Has anyone made any progress in this matter? Thanks
P.S. i have dosdude's DEMUX mod
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Could you post a link to share with the rest of us as well? many thanks.
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I disabled my gpu on my macbook pro late 2011. I originally used a high sierra drive to boot with that had the gpu disable program on it. After my gpu was disabled I put a new ssd in the macbook and installed catalina patcher. Everything is working and I have brightness / sleep function. I was wondering if the gpu disable program is stored on the hard drive or if it does not matter to swap out the hard drive once you disable the gpu? Thank you for any info.
Hi all! You can try my version of CoreBoot for MacBookPro 8.2 with GMUX physically disabled. I run Windows 10/11 on it, but there are problems with the not very responsive trackpad and hibernation. I recommend turning hibernation off by
Code:
powercfg -h off
Bash:
sudo flashrom -p internal:boardmismatch=force -c "MX25L6406E/MX25L6408E" --ifd -i bios -w '/path/to/coreboot/coreboot.bin'P.S. You can rollback to the dosdude1 version by simply replacing the file name in the command with the file from dosdude1
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If thats the case, wouldnt it make your machine identical to a MBP8,1 then? in which case you should be able to just run the MBP8,1 rom? Is the backlight register address different?
Also, just curious (as I havent actually tried it myself), do those ACPI devices (light sensor/etc) works in the MBP8,1 at all?
Hi! Thanks for sharing your coreboot port! Unfortunately afaik it won't run on a 8,2/8,3 with gmux disabled in software, but i might give it a try next month. I'm preparing an exam and I can't afford to have my pc break on me rn
It would be nice if @dosdude1 gave us his sources, to make coreboot work on machines with his mod. tnx
Hello everyone,
I would like to kindy ask for help. The problem is I tried this modification (with wiring to be precise) and failed twice.
If someone could help and tell me what could possibly go wrong I'll appreciate every single response form you.
Problem is I tried wiring the gMux on A1286 15" board. I have read the instruction and begin to solder the wires. I used thin circa 1 mm diameter wire from pulse transformer and while I was soldering I have used board heater set to preheat my board to 60°C. On finish I've double checked every single line if it's soldered correctly.
Everything looked fine so I installed the board and tried to boot the system. When I realised that there is no OS on my drive I have to boot macbook with Command (⌘) and R pressed.
For a bit of time I could use my device with no problems but after about 2 minutes the sceen started to flicker only to turn into white screen. When I tried to reset the system there was no picture at all. Only full bright backlight (white screen).
I fought that my preheater damaged PCH. Is it possible that rising temperature of a board may damage PCH?
After first fail I decided to wire second identical board which has the same problems with dGPU.
This time I've not used my preheater to rise the temperature of the board for better soldering. The same thin wire from transformer. Again after work, double checked the wires and installed the board.
After a few minutes of working I had the same problems! Screen starts to flicker only to lose display. This time I menaged to notice that pressing down in the location where USB ports are, macbook stopped losing the display.
What gives? Is it possible that on my two boards, both PCH have bad solders/are damaged? I have no idea what to do.
This is my first post, I hope there is no problem to continue this thread. Also sorry for my english, I'm from Poland by the way
I attached videos showing problem with first board and second board when I show what is happening when I press the USB device a little more. Thanks in advance.
I would like to kindy ask for help. The problem is I tried this modification (with wiring to be precise) and failed twice.
If someone could help and tell me what could possibly go wrong I'll appreciate every single response form you.
Problem is I tried wiring the gMux on A1286 15" board. I have read the instruction and begin to solder the wires. I used thin circa 1 mm diameter wire from pulse transformer and while I was soldering I have used board heater set to preheat my board to 60°C. On finish I've double checked every single line if it's soldered correctly.
Everything looked fine so I installed the board and tried to boot the system. When I realised that there is no OS on my drive I have to boot macbook with Command (⌘) and R pressed.
For a bit of time I could use my device with no problems but after about 2 minutes the sceen started to flicker only to turn into white screen. When I tried to reset the system there was no picture at all. Only full bright backlight (white screen).
I fought that my preheater damaged PCH. Is it possible that rising temperature of a board may damage PCH?
After first fail I decided to wire second identical board which has the same problems with dGPU.
This time I've not used my preheater to rise the temperature of the board for better soldering. The same thin wire from transformer. Again after work, double checked the wires and installed the board.
After a few minutes of working I had the same problems! Screen starts to flicker only to lose display. This time I menaged to notice that pressing down in the location where USB ports are, macbook stopped losing the display.
What gives? Is it possible that on my two boards, both PCH have bad solders/are damaged? I have no idea what to do.
This is my first post, I hope there is no problem to continue this thread. Also sorry for my english, I'm from Poland by the way
I attached videos showing problem with first board and second board when I show what is happening when I press the USB device a little more. Thanks in advance.