Q: Multiple display problem in OSX 10.9.2

Is there a way to hack this back into working order for the time-being?  Maybe by getting a file/driver from 10.9.1 and overwriting the new one?

Also, someone mentioned changing a DisplayPort compatibility setting, but I don't know how to change that.

Not sure about all vid cards or macs. I was able to get my new mac pro working by looking at which video extensions (ati in my case) were loaded in system information when the monitors were working fine and installed them in 10.9.2 using Kext Utility.

Try reading the instructions that came with your monitor. The setting, if available, is on the monitor.

It's a bug in the OS. Verified with Apple.

Thanks for the info.  Any chance you could help me learn how this is actually done and where to get the files?  Thanks!

Apple support gave up and recommended trying to downgrade back to 10.9.1 until they can release a fix.  No timeline provided.

I was thinking that rather than downgrading the entire version, maybe we could just go back to the 10.9.1 display extensions/drivers, but I don't know how to do this.

Anyone know how to revert display extensions/drivers?

Mine's a 15" MBP with AMD Radeon HD 6750M 1024 MB graphics.

In System Information, sorting extensions by date reveals a few graphics-related ones that were updated during my update to 10.9.2, which seem like they might be the culprit (though I have no real idea of what I'm talking about here):

• AppleGraphicsDeviceControl
• IOGraphicsFamily
• AppleGraphicsDevicePolicy (not loaded)
• AppleMGPUPowerControl (not loaded)

I don't have access to a machine like mine with 10.9.1 extensions.  Is there a place where I can get these?

Do you have a time machine backup? That's where I dug mine out of.

I have ATI cards in mine but the idea might work for others. First I looked at t extension list in the System Information app and looked at the AMD (ATI) drivers that were loaded (see pic)

I then then pulled all of the AMD drivers and files from a known working time machine backup and installed them using Kext Utility and it worked. After some trial and error, I managed to isolate it to 5 files.

Link for Kext Utility

Same problem here.  My monitor is a Crossover 27QW and why Apple can not provide quick solution to fix it ?

Replaced AMDSupport.kext with old one and can not boot

What's files did you replace ?

thanks

That single file is not enough. You need to replace all the loaded AMD files. Screen shot shows which ones are loaded for me on my late 2013 mac pro. Your's may differ. Should be able to just replace all the amd files.

I was able to solve this issue for myself by setting my display to only use DisplayPort 1.1 rather than DisplayPort 1.2

iMac 21.5 late 2009, connected to a Sony TV Bravia (MinidisplayPort>Hdmi).

after upgrade to 10.9.2 monitors are mixed up: Now the Sony TV is the  main monitor 

System info: (status: Mirror on, Mirror Master) and iMac is the secondary display ( status:mirror on, mirror Hardware)

I tried to switch back but there is no way to do that and arrange the right configuration. At times I have the dock on one display and the task bar on the other. Monitor profiles are inverted and  System Preference panels only opens on the main display (TV),   so I am afraid to restart the iMac.

Filed a bug report to Apple but in the meantime I would like to be  back in control on my iMac.

Any idea?

I had the same problem on my 2009 MacPro and resolved the issue by disconnecting both the display port connector and the USB connector from the display's wiring harness and then reconnecting the display port first and the USB second. Apparently, the USB has to communicate the fact that the display is available before the computer can recognize it.

I'm in the exact situation you are (new 2013 mac pro, upgraded to 10.9.2, broke external display with mini displayport -> dual link dvi). But, unfortunately, I don't have access to a time machine backup (and, thanks to apple, we no longer get DVD drives with install DVDs ). Do you know where I could get those 1.20.7 drivers elsewhere? If you'd be willing to share your drivers I would be super thankful.

I don't think that sort of file sharing is allowed on this site. Wish there was a way to send you a direct message.