Mavericks 10.9.3 Update Has Disabled Two of My Quad Monitors

I am betting you powered off all four monitors after a cold shutdown, powered them all on, and then rebooted. Did that re-enable those 4 monitors?

When I see the two words, “conversion kit,” it may suggest you are doing something that Apple engineering either did not support (and you got away with it until 10.9.3), or they did not consider your configuration as a permutation that they should support, or a bug got through.

I would submit MacPro feedback to Apple. If you clearly state your MacPro, monitor, conversion kit, and other pertinent facts, this may help them help you. Sometimes, the feedback initiates contact to further clarify the issue, and if you are fortunate, this may be your case. In the interim, I would directly contact Apple and see if they can help (sooner).

I have the same issue with a similar setup.

I have the Late 2013 Mac Pro, and before 10.9.3 I was able to connect my 4 1680x1050 Dell displays to my mac pro via active dvi -> mini display port adapters.

It has always been the case that with passive dvi adapters you could only run 2 at the same time (or 1 + the hdmi out)

Using active adapters allowed you to connect more than 2 DVI displays.

But this seems to have been what has broken under 10.9.3

Now even with active adapters only 2 dvi displays will work at a time.

Just want to note that it's clearly an issue with 10.9.3 on the new Mac Pro.

My displays still continue to work great under Windows/Boot Camp, but they are pretty useless to me there.

Im having the same issue

Exactly the same issue

Some knowledge base articles that may add clarity to your monitor support woes.

Mac Pro (Late 2013): Using multiple displays.

Using 4K displays and Ultra HD TVs with Mac computers.

And for those on the Boot Camp side with a Mac Pro, late 2013:

Mac Pro (Late 2013): Using multiple displays on Windows 8 via Boot Camp

Make certain you have the latest SMC and EFI firmware updates here. If yours match or are newer, the updates will simply tell you that they will not install.

Apple clearly broke multi monitor support in this upgrade, the KB articles are not going to help.

Only solution for now is to go back to 10.9.2 (if you have a backup) and wait for a fix.

If you can't go back, someone solved it by removing the ati and nvidia kexts installed by 10.9.3 and replacing them with the 10.9.2 ones.

I am told that putting older kexts into newer osx may be illegal, so don't do that.

Am now being helped solving the issue by Apple support. Will post the solution when/if they find it.

Cheers

Any fixes found yet? I have the same problem. I literally recieved my dual-lik adapter today, had everything working on 10.9.2, and then installed 10.9.3 about 15 mintues ago. So, I had three DVI monitors working for about... 2 hours. Now back to 2. Very frustrating!

Nothing yet. Spent an hour and a half on the phone with tech support trying various things, but nothing worked.

They are testing 10.9.4, so maybe that will solve our issue.

Moral of the story: I love TIME MACHINE 🙂

I had the same problem with a new Mac Pro. I had 5 Active DisplayPort DVI adapters plugged in and working fine but as soon as I applied the 10.9.3 update only two of the DVI outputs would function. I reset the PRAM and did NVRAM resets, permission checks and all the other usual tools. Any two of the mini DiplayPort outputs will work, but only two. I have a support case open since 5/18/14 with no news other than "it's being worked on."

Same issue here but with no adapters. I have 2x 4K samsung 28 inch monitors, 2 Apple TB Displays and 2 dell u2711. Only 3 at a time work, doenst matter what combination. On top of which, after updating my late 2013 15MBPr to 10.9.3 he can only support ONE at a time. Doesnt matter 4k or not via TB.

Seems a bit like a joke when my 13 inch can support 2 4k monitors on its Iris GPU :-)

Same issue here!

Btw there was already a discussion in February about these isssues and it got even worse.

https://discussions.apple.com/thread/5839209?answerId=24975964022#24975964022&ac_cid=tw123456#24975964

I cannot believe that !

It's already a farce that you have to buy 4 active Apple adapters for connecting multiple monitors of which two are now wortthless?!

On WIN8.1 under bootcamp you just need (1/3 priced) standard ACTIVE adapters to get six outs (ok, I am talking here Single-DVI for for 4x HD).

And btw. the speed of the GPUs under WIN8.1 can be added via Crossfire settings... (which I can't even compare under 10.9.3 because i am only able now to connect two displays...)

What are you doing here Apple?

This is currently really breaking my business ! ! !

djbene

I just wanted to add that I sent a Bugreport to Apple about this issue: #17031910.

Could not edit my original posting (?!).

djbene