May 15, 2014 at 7:14 pm
Unless I’m missing something it appears that Mavericks 10.9.3 tightened the parameters on using multiple monitors and I can’t run all three monitors that I could run an hour ago before the OS update.
I’ve got a new 2013 Mac Pro. I’ve been running three monitors; two 30″ monitors using the Mini DVI to Dual Link Display port adaptor here:
..and an output monitor on the HDMI port.
After the 10.9.3 update the new Mac Pro will only recognize two monitors. Any two but only two.
I have not change the arrangement of the ports either. I have the two 30″ displays plugged into (1) the upper left TB port and the other (2) is in the upper right TB port. This puts them on separate buses. The HDMI port has nothing plugged into it (this includes the bottom two TB ports on the same bus as the HDMI port) except an HD monitor.
The Displays preference pane will only see two monitors after the OS 10.9.3 update.
Or, am I missing something?
May 15, 2014 at 8:20 pm
All fine here with my rMBP. Had to use alt-key in display prefs for my HP Dreamcolor to change the res back to 1080p to use it as my third monitor and full screen output for FCP X through the HDMI port.
May 15, 2014 at 8:40 pm
Jari, I suspect that the update doesn’t like the 30″ monitors I’m running even though they are connected using an active adaptor. But it worked before the update. Please know that I’m not saying the update won’t run three monitors. I’m just saying it won’t run my set of three monitors.
May 16, 2014 at 12:10 am
I have the same problem here. Two 24″ NEC screens and a 30″ Dell U3011 which is connected via the fancy powered adapter.
I can only have two screens working at once. Eg after I upgraded to 10.9.3 the 30″ was black but both the NECs worked. Disconnected one of the NECs and the Dell worked.
Looks like no Apple developer uses more than two screens. And no-one in the public beta program either.
If you are a developer, file a bug report so that hopefully it will be fixed soon. That’s what I’m doing.
May 16, 2014 at 12:54 am
I, too, can confirm this issue with a new Mac Pro with dual D500 video (doubt that matters though).
As soon as I upgraded to OS X 10.9.3, I lost my third display. I’m using 3 identical 27″ LG monitors running at 1920×1080 resolution. One connected directly via the HDMI port on the Mac Pro, one via a Mini-DP to HDMI passive dongle/adapter, and the third via Apple’s $99 Dual link DVI to Mini-DP adapter.
This especially irritates me because I never ran more than 2 displays before, until I invested in this new Mac Pro. That’s when I decided I may as well splurge with it and get a third matching display screen, and a triple monitor VESA mounting bracket to put them on. That’s when I discovered the nMP had the limitation of requiring one of your connections to be active vs. passive if you want more than 2 displays, so I went out and spent the $99 on the dual-link DVI to Mini DP contraption. Now, only a few weeks after getting that all going — I’m back to 2 monitors again anyway!
I did file a bug report with Apple, BTW. We’ll see how quickly this gets fixed ….
May 16, 2014 at 2:56 am
Mavericks 10.9.3 has also affected dual display on my early 2009 Mac Pro. At first only one monitor responded. The menu bar was greyed out and I couldn’t move the cursor across the two displays. I went into System Prefs and tried dragging displays, gathering displays, mirroring all to no avail. I then restarted, tried it again and it appears to be working now. However, Monitor # 1 is on the left and # 2 on the right. I can’t seem to swap them. For some strange reason I had set # 1 on the right and #2 on the left.
I just finished working on a project last night. At first glance, FCP X appears quicker, more responsive after upgrading to Mavericks 10.9.3.
May 16, 2014 at 10:35 am
Same thing here. Using 2 19″ Samsung with active dualinl dvi- mini display and 40″ Samsung to HDMI all on separate busses! Completely absurd on Apple’s part.
May 16, 2014 at 6:38 pm
Same here… Lost my second monitor
10.9.3 killed my second monitor (Dell U2412M)
Now I can only boot into one or the other (Primary is a 27″ LED Apple Display).
Late 2013 Mac Pro with dual D700s
Encouraged to hear some people are running two monitors. I’m on separate busses for each but can only restart into one or the other 🙁
May 17, 2014 at 1:44 pm
More info here: https://discussions.apple.com/message/25803326#25803326
May 19, 2014 at 6:42 pm
Downgrading to 10.9.2 via the recovery drive(without affecting any installed apps&plugins) seems to be the best quick fix. Apple Senior Tech.’s recommended as well.
And to be fair Applecare’s response was quite good and helpful. Hopefully it’ll be fixed soon; so we can upgrade.
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