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Level 1

12 points

Multiple Displays have problems with El Capitan

I upgraded to El Capitan last week. Immediately after restarting from the install, my 2nd and 3rd monitors no longer displayed anything. It's like they were turned off. I tried restarting, but nothing changed. I then tried switching cables to different ports and seeing what would happen with just a single monitor plugged in, here's what I found.

Machine Info:

MacPro

32GB RAM

AMD FirePro D500 3072 MB Graphics

27" Apple Cinema Display (x2) using Thunderbolt

13HD Wacom Cintiq using HDMI

-------------------------

When 1 monitor was plugged in, it would work fine.

When 2 were plugged in, only the first monitor would work

It seems that changing ports made no difference, only 1 monitor would work at any given time. I also had issues with some external drives failing to mount.

I called AppleCare and they had me reset the SMC on the MacPro. This seemed to fix it until I setup my second cinema display with Apple Calendar and Apple Mail in the new split view and quit the applications without exiting SplitView first. Doing this blacked out the second Cinema display and I had to repeat the SMC reset procedure (listed below). It happened again about an hour later after a restart, I called AppleCare again and the tech led me through the SMC reset steps again and all monitors began working properly again. Within the next few hours the same problem happened again...I am now back on Yosemite until I see something indicating this problem is fixed.

I noticed that Beta users had this problem documented quite a bit on the .3 release, but I saw that the .4 release seemed to fix the issue. Well, it did not. I caught lightening in a bottle and it's happening to me.

SMC Reset Procedure

1. Shut Down computer if it's not already shut down

2. Unplug all peripherals and computer for 30 seconds

3. Plug in computer to power and one monitor

4. Start-up and check to see if monitor is working

5. If monitor is working then plug-in second display and restart

This worked for me and I was able to plug up the other peripherals.

I'm not sure why the problem persists, but everything is completely stable and operates fine on Yosemite.

Mac Pro, OS X Yosemite (10.10.5), iMac 27" 8GB i7

Posted on Oct 5, 2015 9:34 AM

156 replies

Oct 5, 2016 8:31 AM in response to elcapitanbambino

It's like the Sith saying, go to sleep. On my perfectly beautiful Wacom Cintiq, when their iPad Pro's pen is only like 25% as good, seriously. I don't like star-wars that much though.

Oct 5, 2016 9:02 AM in response to elcapitanbambino

Also note: Apple's DVI-I -> MiniDisplayPort was probably an early ThunderBolt compatible cable and needs to be updated or replaced with something in the 4K range, version 1.2 of cable.

Hence why I got DisplayPort to Mini-DisplayPort. It'll take a bit, you can find a work around, look at all the steps I pointed out. Hopefully "It Just Works", again as they used to say.

Oct 17, 2016 11:33 PM in response to funambule

After some time searching I found a solution that worked for me.

Somehow I stumbled on the Nvidia "web" driver for Mac. The story is that Apple does not always update the video driver with OS. Improved video driver is available from Nvidia web site, although it is not officially supported by Apple. I was a bit worried when I downloaded and installed it, because there are so many versions and warnings, plus it's not straightforward to find the latest driver on Nvidia site, but in the end it just fixed my issue with the external monitor. Now display is fine, I can unplug/plug the monitor and image is fine.

Here is the download link:

http://www.nvidia.com/download/driverResults.aspx/107369/en-us

Version of OS El Capitan: 10.11.6

JTN11

Level 1

4 points

Nov 3, 2016 9:03 AM in response to Mattzda3

This process worked to reconnect my display. Thank you.

SMC Reset Procedure

1. Shut Down computer if it's not already shut down

2. Unplug all peripherals and computer for 30 seconds

3. Plug in computer to power and one monitor

4. Start-up and check to see if monitor is working

5. If monitor is working then plug-in second display and restart

Nov 11, 2016 7:02 PM in response to JTN11

New to this discussion and apologize if the answer is buried in the 11 previous pages.

Trying to watch a DVD on television screen (hooked up through VGA) and continue working in other apps on my MacBook Pro display. Mirror display option has always worked.

Tried without success to go through steps using Mission Control and Display in system preferences.

Machine stats:

MacBook Pro (early 2011)

El Capitan 10.11.6

Thanks, Suzanne

Nov 12, 2016 5:17 AM in response to suzannepdx

suzannepdx wrote:

New to this discussion and apologize if the answer is buried in the 11 previous pages.

Trying to watch a DVD on television screen (hooked up through VGA) and continue working in other apps on my MacBook Pro display. Mirror display option has always worked.

Tried without success to go through steps using Mission Control and Display in system preferences.

Machine stats:

MacBook Pro (early 2011)

El Capitan 10.11.6

Thanks, Suzanne

So what exactly is or is not working now? Don't you have any image on the TV?

Does the TV appear in System Preferences->Displays or is it not even being recognized?

Did you try holding down the option key while in system preferences->Displays and click the Detect Displays button?

Multiple Displays have problems with El Capitan