iMac2010 with gtx765m - black screen after reboot

[kingvald]

Hi, just installed Big Sur on my 2010 iMac with a gtx765m graphics card. Everything works fine except when I reboot the iMac display stays black.... my secondary display works fine (connected via display port). To get my iMac screen to work I have to press alt when rebooting and select my system volume.... then the iMac screen works...

Any fix for this?

[Ausdauersportler]

Yes, check this fork ...or patch the AGC yourself using this command after making root writable (docs online, at the very end of it)

/usr/libexec/PlistBuddy -c 'Add :IOKitPersonalities:AppleGraphicsDevicePolicy:ConfigMap:Mac-F2268DAE string none' AppleGraphicsControl.kext/Contents/PlugIns/AppleGraphicsDevicePolicy.kext/Contents/Info.plist
/usr/libexec/PlistBuddy -c 'Add :IOKitPersonalities:AppleGraphicsDevicePolicy:ConfigMap:Mac-F2238AC8 string none' AppleGraphicsControl.kext/Contents/PlugIns/AppleGraphicsDevicePolicy.kext/Contents/Info.plist
/usr/libexec/PlistBuddy -c 'Add :IOKitPersonalities:AppleGraphicsDevicePolicy:ConfigMap:Mac-F2238BAE string none' AppleGraphicsControl.kext/Contents/PlugIns/AppleGraphicsDevicePolicy.kext/Contents/Info.plist
chmod -R 755 AppleGraphicsControl.kext
chown -R 0:0 AppleGraphicsControl.kext

Cannot tell you which line is yours, all three do not harm at all....it is the board-id of your iMac added to the plist

[hadnet]

I'm having the same problem with an iMac mid 2011. Tried the commands above but does not work.

[Ausdauersportler]

You need to add your own iMac 2011 board-id instead to the Max 2010 one used in the commands. The general code would be this (copied from the iMac micropatcher)

MYBOARD=`/usr/sbin/ioreg -l | grep board-id | awk -F\" '{ print $4 }' | grep Mac`
/usr/libexec/PlistBuddy -c "Add :IOKitPersonalities:AppleGraphicsDevicePolicy:ConfigMap:$MYBOARD string none" AppleGraphicsControl.kext/Contents/PlugIns/AppleGraphicsDevicePolicy.kext/Contents/Info.plist
chmod -R 755 AppleGraphicsControl.kext
chown -R 0:0 AppleGraphicsControl.kext

The best long term strategy would move over to OCLP - it should give you a 100% supported feeling with working OTA upgrades.

[hadnet]

If I try installing with your fork do I need to run that command line as well?

[Ausdauersportler]

No! It is included and the patcher should recognize your hardware and enable all patches automatically. I have added all changes needed for iMacs with modded GPU. Check out the docs.

Which GPU do you have?

[hadnet]

Same as kingvald, GeForce GTX 765m 2gb by Nick[D].

[Ausdauersportler]

Did you update the BIOS to have brightness control?

In that case you would need OpenCore to enable it.

So your only options are again the 0.5.4 fork with OpenCore or OCLP to get all done in one sweep.
Honestly I ask you to try OCLP. I will maintain this my fork but not develop on it.

[hadnet]

No, I did not. Installing with USB still black screen and need to hold Option, but running the command you tell me (MYBOARD...) now it works perfectly. How can I get bright control using your fork? I don know what opencore or OCLP mean and how to do that. Thanks for your help, man, really appreciate it.

[Ausdauersportler]

First you need to flash the new vBIOS onto your card.

Then you need to enable OpenCore by using the

1. OCLP (Do no forget to enable the NVIDIA metal GPU patch in 5. Patcher options.)

or

2. the iMac Micropatcher fork using the opencore setup.

BUT:

The OCLP will get you brightness control and upgrades using Apple Software Updates. No more reinstallation on each new versions.

You need to read the docs coming with each solution.

[hadnet]

So in order to get brightness control I need to follow this part of the doc?:

“Instead of install-setvars.sh all users of iMacs Late 2009, Mid 2010, and Mid 2011 using metal GPU have use the install-opencore.sh command in the very same way as described above. It will install a preconfigured opencore using the @khronokernel patch to boot iMac Late 2009, Mid 2010 as well as all MacBookPro 6,x models (2011). This version is needed only during installation and has to be changed later using config-opencore.sh after step 15. Whenever you want to use the USB installer to do a fresh installation repeat this step 7 and do a PRAM reset to delete the old OpenCore settings from the NVRAM.”

[Ausdauersportler]

Yes!

But as I said before you are probably better suited with the OCLP. Everything I added to my micropatcher went into OCLP, too. There was no gain in having two nearly identical developments competing for users.

I will use the micropatcher in future only a a development vehicle, not so much to provide new versions.