Multi Monitors on Yosemite

[supraTT]

This thread is intend to be to the place for people who has multi monitors set up to share about their experience on set up more than one monitor on OS X 10.10 Yosemite whether success or failure, question, problem that you'd like to share.

 

I have dual monitors that capable of doing 2560x1440 @60 hz that connected to the AMD Radeon R9 270 via both HDMI and DVI-D under Windows 8.1 they work perfectly but on Yosemite only one monitor works at a time never both at the same time.

 

What I did what edit the AMD7000Controller.kext and AMDRadeonX4000.kext to add the device ID (R9 270 ID is 68111002) into the info.plist as describe by this thread 

http://www.insanelymac.com/forum/topic/294315-radeon-r9-270x-framebuffer-issue/hl=%20r9%20%20270

The process is copy the two kexts to desktop then edit: for AMD7000Controller.kext

 show package content->Contents->info.plist->IOKitPersonalities->Controller->IOPCIMatch then add/modify 0x68111002

for AMDRadeonX4000.kext

 show package content->Contents->info.plist->IOKitPersonalities->AMDPitcairnGraphicsAccelerator->IOPCIMatch then add/modify 0x68111002

then use Kext Utility app to install the two kexts, reboot if you use clover as a bootloader add kext-dev-mode=1 for kernel argument in the option menu

 

note: install Xcode 6 would make it easier for editing the info.plist, 

you also have to do this again every time you do system software update 

 

Here the result of my Cinebench r15: openGL 106.88 fps, cpu 709 cb 

 

Anyone get the dual monitor working on Yosemite?

[Sensei07]

Hi supraTT,

 

I'm on it. I tried to replace the AMD7000Controller.kext in Yosemite with the one of Mavericks because there all worked fine out of the box.

 

A few minutes ago I found your thread and I'll try this one in a couple of hours. 

 

I'll come back to that with my results when I'm finished.

 

Yours seemed to work :-)

[Nameless One]

With Intel onboard enabled, and Clover injecting the R9 290X ID in place of R9 290, no kexts modified, I have a 30" and a 23" monitor attached to the R9 290 (DVI & DP) and a 23" to the Intel onboard (DVI) everything working fine. If I didn't want to mess with the BIOS or fiddle with Clover during boot I could attach the second 23" to the second DVI on the R9 290 and boot blind.

 

Rather disappointingly I get 86.82 fps (the fans don't ramp up at all and it labels the card as some Hawaii prototype) and 547 cb in Cinebench R15 (for some reason it says the CPU has 2 cores, 4 threads)

75.79 fps with the window on the display plugged into the onboard Intel HD4600

 

Intel i5-4670

Asrock H87 Fatal1ty Pro

16GB DDR3 1600MHz

Powercolor PCS+ R9 290 4GB

[d620osx]

Hi

 

I have dual monitor's working fine with my hd5450 and clover. I could not get the gpu to work correctly with chameleon.

 

I did have to add the id for my card to the amd300kext to get it all working.

[gateway69]

Anyone have 290x working in Final Yosemite, I can get one DVI working but the moment I plug in another monitor via dvi both screens go black... Im using Clover

[aicragleon]

To get 290x with dual monitors / multi monitors (works with 3 for me) boot with one monitor, put computer to sleep, then plug in 2nd monitor (or 2nd and 3rd), then wake the computer, profit. 

I have a 290x on Yosemite using Clover with an x79 board. I found this out after hours of troubleshooting. The only thing I changed in the config.plist was to use Hawaii framebuffer, and if you have a problem with dual monitors then you probably don't have to worry about this since I have the same problem as everyone else. Tonight I will experiment with a script to put the computer to sleep at bootup to see if having 3 monitors connected will work after sleep and wake, or if OS X has to boot with only one monitor. This answer will come soon since I am on my way home now. The script was from the old 7970 days when a sleep trick was the fix for that. I will post the source for this and instructions on my next post.

[Pavo]

To get 290x with dual monitors / multi monitors (works with 3 for me) boot with one monitor, put computer to sleep, then plug in 2nd monitor (or 2nd and 3rd), then wake the computer, profit. 

 

I have a 290x on Yosemite using Clover with an x79 board. I found this out after hours of troubleshooting. The only thing I changed in the config.plist was to use Hawaii framebuffer, and if you have a problem with dual monitors then you probably don't have to worry about this since I have the same problem as everyone else. Tonight I will experiment with a script to put the computer to sleep at bootup to see if having 3 monitors connected will work after sleep and wake, or if OS X has to boot with only one monitor. This answer will come soon since I am on my way home now. The script was from the old 7970 days when a sleep trick was the fix for that. I will post the source for this and instructions on my next post.

290x device id is in AMD8000Controller.kext not AMD7000Controller.kext and there is only Exmoor and Baladi Framebuffer in the AMD8000Controller.kext, there is no way possible to use the Hawaii framebuffer with the 290x even if you delete the AMD8000Controller.kext and manually put the device id in the AMD7000Controller.kext or use a fakeid with Clover it will do nothing but give KP. Also the default framebuffer that is used for the 290x is called RadeonFrambuffer. I currently have DP, HDMI(w/ audio), and both DVIs working on my 8Gb 290x you can look at my patch here:

http://www.insanelymac.com/forum/topic/297728-r9-290x-help-for-mavericks/?p=2110681

[lethanhtung]

I have the same vga R9 270 w ID 6811 but i cannot boot into yosemite w HDMI (only DVI). Did u modify AMD FB as this Topic (http://www.insanelymac.com/forum/topic/303186-how-to-modification-of-amd-fb-clover-injection/) and injectATI=true or false??? Thanks so much..

[letThemPlay]

I've managed to get multiple monitors working on my R9 270, however they are daisy chained via displayport.

I had to add my device id to AMD7000Controller.kext and AMDRadeonX4000.kext; for some reason even though I put them back via kext utility and using the kext-dev-mode flag in clover; I have to have them in my kexts folder in clover or it doesn't load properly.

 

I also use the Hamachi framebuffer which was the only framebuffer I found that consistantly gave me both displays. I tried patching the framebuffer using the method in the another thread; however when I do this my monitors just go to sleep when I boot up.

 

I do have a rare issue where maybe one in twenty boots the second monitor doesn't turn on correctly; where I have to reboot to fix it; but other than that its working great.