Q: Mac Pro 2013 Multiple Display Issues

I have exactly the same experience! I returned the first Mac Pro within 14 days and got a replacement from Apple Store on the same day.The replacement computer has the same wakeup and freeze problem. I have been working with Apple Engineering team since mid June.

I demanded a full refund today. Apple claimed that this new Mac Pro would be able to support 6 monitors. But I can only get one to work. If they don't give me my money back, I will have to take them to a small claims court!

Its turned from not only refusing waking from sleep but also if I restart it will freeze on the grey apple and I have to hard restart. The only way that it will work 100% of the time is if I fully turn off my system when I am not using it as a fresh startup works great. Hopefully this means its just a bug in the software and not the hardware.

Has anyone heard anything regarding this issue? My third monitor has suddenly stopped working after a reboot last night. I've tried everything, from completely powering down my Mac Pro to reinserting all the Mini DisplayPort cables. Nothing... I'm getting VERY annoyed, as this is my primary work machine that originally cost $5,000+. Why isn't someone from Apple at least chiming in?

Volt-Mac:

Whats the issue Apple, get some people on this - Please.

This is a User-to-User forum, and there are no procedures for escalating the problems you note here.

If you want  Apple to take notice of your problem and begin working to solve it, you need to contact AppleCare by taking all your gear into the Genius Bar at an Apple store, or by contacting telephone support (90 days free with the serial number of a qualified Mac).

I just submitted by feedback at http://apple.com/feedback

I'm just amazed that we're still dealing with such a serious issue. It's obviously an OS X bug.

Same issue with me, I have 2 Asus PB278Q monitors on my new mac pro. My problem is on start up as well, only 1 monitor will activate upon startup and the other monitor will need to be turned off and on again to active. This happens on every start up, not just once in a while. I turned off sleep because I couldn't handle this issue.

I don't want to send this computer back to apple, because this is so wide spread and seems like a software bug either in the OS or the graphic card firmware. Also, sometimes my wallpaper will get reset, resolution will get reset and even arrangement on start up. Once the actual machine has started everything is usually fine. It is just during sleep and start up where it has these issues.

Interested if anyone has updated to Yosemite and if this fixes the problem?

I've seen variations of this problem on my nMP.  It had seemed like Yosemite fixed them but it was temporary.  With 10.9.4, I had the dual monitor boot problem.  With 10.9.5, the dual monitor boot problem appeared to go away, but I would get random screen glitches where the screens turn grey or fill with garbage for a minute and the machine would lock up about half the time when that happened.  I'd also occasionally get the machine not waking from sleep.  With Yosemite, the dual monitor boot problem continued to appear fixed.  The screen glitches continue, but typically subside without having to restart the machine, but the sleep lockups have gotten much worse and occur even with only a single monitor hooked up.  I've had this machine into the Genius Bar already once for a hardware diagnostic and they found nothing wrong.  I'm going to try different monitors to see if they help.

I am running the release version of 10.10 on my nMp 6-core 3.5 GHz 64 GB RAM 1 TB SSD and dual D700s with multiple monitors without difficulty.  I usually run two non-Apple 30" monitors and occasionally an additional three 24" monitors (normally used by a Windows PC for work), all without difficulty and none of the problems described in this thread.  The only time I had a problem was when I was using a non-Apple mini display port cable with intermittent recognition of the monitor.  Now all Apple cables without a problem.  Yosemite has been rock solid without any crashes.

Good to know that it does work fine for some people.  In my case, I've used both Apple and non-Apple cables.  I could believe that non-Apple cables could have issues but that doesn't seem to be the case.  I'm going to test with a Thunderbolt display and a Dell UP2414q this weekend. 

Disappointed....

Upgraded to Yosemite and the sleep / wake problem is still there. When I restart both come up as they should which is some improvement as it used to only work on a full shutdown.

has anyone made any progress on figuring out this issue?

I'm on 10.9.5 and didn't have any issues for a couple months, then the issue started up again; I have to restart my computer each morning whether I want to or not, because one monitor shows up as a black screen and the other monitor flashes between two different desktops trying to figure out if its in dual mode or not.

I can put the displays to sleep (Opt Command Eject) and wake them up and it will be fine. But its something about being left alone overnight that makes the monitors freak out. I originally thought it was just display sleep in general...

Have you tried just turning off and then back on your monitor? I have to do that sometimes.

Yes. I would love it if it were that simple!
I have tried unplugging it even. Unplugging the blank monitor wiill get the other one to stop flashing back and forth, but it doesnt fix anything when I plug it back in again. I have to restart completely. (actually havent tried logging out instead, but that would still be a pain to do each time)