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ArchStudent

macrumors newbie
Original poster
Jan 31, 2020
15
1
Hello,

This is for anyone who has had a or currently has a Mac Pro 3,1 with an R9 280X gpu that has been flashed with the Mac efi.

When using a flashed R9 280X gpu with mac efi, are there any issues with the compatibility with the 3,1 (for any OS version) being finicky or picky and not working properly? Having boot issues or screen issues, or sleep issues?

thanks for your replies!
 
Hello,

This doesn't answer your question directly, but I used to run my 3,1 with an R9 280x. It works out of the box with zero problems, with total compatibility and excellent performance. The only thing you miss is the startup screen. Why not give it a go stock?
 
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Ph.D., if you don't mind my asking, which R9 280X card and version of OS X were you using?
 
I know there are zero issues with the R9 280x is my 5,1’s. I was not sure if the 3,1 had potential issues or not.

I have several cards: Gigabyte windforce, MSI, XFX versions and the Sapphire version of the R9 280x cards. All of them work flawlessly in High Sierra, Mojave and Catalina.

They have all been flashed as well :)
 
I know there are zero issues with the R9 280x is my 5,1’s. I was not sure if the 3,1 had potential issues or not.

I have several cards: Gigabyte windforce, MSI, XFX versions and the Sapphire version of the R9 280x cards. All of them work flawlessly in High Sierra, Mojave and Catalina.

They have all been flashed as well :)
There is a power management bug for 280X on 3,1. That will make the 280X can only perform at about 50%.

The work around is simple, just remove the AppleIntelCPUPowerManagement.kext and AppleIntelCPUPowerManagementClient.kext.
 
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There is a power management bug for 280X on 3,1. That will make the 280X can only perform at about 50%.

The work around is simple, just remove the AppleIntelCPUPowerManagement.kext and AppleIntelCPUPowerManagementClient.kext.

Thanks for that info. I'm curious, do you know if that power management bug for 3,1 exists just with the R9 280X or does it effect all metal capable AMD cards. Also curious if the Dosdude1 patch for High Sierra and above fixes that power management bug.
 
Thanks for that info. I'm curious, do you know if that power management bug for 3,1 exists just with the R9 280X or does it effect all metal capable AMD cards. Also curious if the Dosdude1 patch for High Sierra and above fixes that power management bug.
AFAIK, Nothing about Metal, this bug exist since Mavericks. It's the driver's issue for HD7xxx series GPU.
 
There is a power management bug for 280X on 3,1. That will make the 280X can only perform at about 50%.

The work around is simple, just remove the AppleIntelCPUPowerManagement.kext and AppleIntelCPUPowerManagementClient.kext.
This tip worked for me in El Cap but not in High Sierra.
 
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I have a AMD Radeon R9 280X 3 GB currently in my 5,1 Mac Pro which I recently upgraded to Big Sur using OC. I also have a 3,1 Mac Pro that's running El Capitan. I'd like to get Mojave running on that machine. I'm wondering if there's been any new info of putting the R9 280X in the 3,1 AND running Mojave. I also use Mountain Lion on that machine from time to time for one app that won't run on anything newer.

Apologies if this has been answered somewhere, searches for up to date info is tough to find. I did come across a 3 yr old thread stating this card will not work on the 3,1. I could always just bite the bullet of trying it, but if anyone has thoughts I would appreciate them. Thanks!
 
Zachránil jsem Mac Pro 3.1 z koše. funguje a nainstaloval jsem přes OCLP Big Sur.
Zkouším vyměnit GPU, ale moc se mi to nedaří. Sapphire R9 280X asi není ten pravý. Po připojení běží ventilátory, ale to je vše, monitor se nezapne, prostě nic. Zkoušel jsem mnoho tutoriálů, ale nic nepomohlo. Nevím, co dělám špatně. Má někdo zkušenost?

i also try to install windows 10 with the same result. USB boot, auxiliary drivers, I have everything, but after restarting and entering boot from USB, I just get a black screen. I really don't know where the mistake is.
 
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