10.9.3 only lets me use 2 of my 3 30" displays

YEEEEEEESSSSS... it works! many thanks gatd4 for the kexts and the instuctions

Install the combo like kinman1 said. Mine was fixed afterwards too.

http://support.apple.com/kb/DL1746

After that you can also try a PRAM reset.

Resetting NVRAM / PRAM

1. Shut down your Mac.
2. Locate the following keys on the keyboard: Command (⌘), Option, P, and R. You will need to hold these keys down simultaneously in step 4.
3. Turn on the computer.
4. Press and hold the Command-Option-P-R keys before the gray screen appears.
5. Hold the keys down until the computer restarts and you hear the startup sound for the second time.
6. Release the keys.

I suspect that like me you have the new Mac Pro, in which case I don't expect shuffling around Nvidia drivers will do you much good because it uses AMD graphics.

I have 4 dell dvi monitors connected via active display port adapters working great up until 10.9.3 and now can only get any 2 displays to work.

I spent some time with support and we were unable to resolve the issue so far.

I tried replicating the nvidia kext hack with amd related kext's but couldn't get my mac pro to boot with older kexts.

The kexts I tried from 10.9.2 were:

AMD7000Controller, AMDFramebuffer, AMDRadeonX4000, AMDRadeonX4000GLDriver.bundle, AMDSupport.kext

Could not get the machine to boot (aside from safe mode) with those replaced (updated permissions/ownership as well). Had to restore the versions from 10.9.3 in safe mode.

Pretty frustrating, but it does seem like they have engineers looking into it now. Hopefully a fix will land soon.

Another big YESSSSSSS! gatd4's kext solution worked perfectly, when nothing else did. My 2008 Mac Pro has its second monitor back.

My only suggestion would be to drop the kexts one at a time on to the Kext Utility window. If you do them all at once, you won't see any progress indication, and it actually does take quite a long time.

Thanks again, gatd4.

One more thing to note, all of my displays remain functional under boot camp.

Still limited to 2 when booting into 10.9.3

frabtious, for information, i have a 2008 Mac Pro with an Nvidia GTX 680 flashed card.

I have the same issue with my 2013 Mac Pro. I already went to downgrade back via Time Machine.

Would you try putting the 10.9.2 AMD extentions back and see if that works? Let me know please.

I uploaded the AMD extentions from another machine that still runs 10.9.2

https://www.dropbox.com/sh/d85ffqgwyaec2u7/AACI9zySnHTW9Bx_qvWk9QSBa

(Foot tapping)... Not fixed soon enough for me, given how many people use multiple displays on MacPros that are not necessarily Thunderbolt-native, doesn't seem like they tested that update too rigorously before pushing it out to people.

The irony for me is that the 10.9.3 update *did* successfully fix my Back to My Mac, which was cutting out every 5-15 minutes and would not reconnect unless I disabled/reenabled Back to My Mac in system prefs. So, um, thanks?

All this cutting-edge Mavericks OS technology is fantastic, if only it would work the way it is supposed to.

I have the same issues. I tried to revert to a time machie backup of 10.9.2 but all the system apps failed to install properly. Im back to 10.9.3 and will try the fix you propose but am unsure where to copy these. Do I copy all them? I am running a new MacPro 2013 with the lowest base video card.

I tried the AMD kext files and it still didnt work

Man that's not cool. I ended up restoring form time machine back to 10.9.2

That is really weird - why it doesn't work.

I took the system apps and any other missing apps back from Time Machine. This is prob not a perminent fix but until they come out with an update, it saved me from an erase and reinstall.

BTW - the apps work fine once moved from my TM backup. It seems that only the apps themselves were lost and not the application support files.

My guess is that TM is meant to reinstall your personal stuff and should be used after a clean reinstall.

Either way, am I the only one who see that the more recept OS updates are plagues with far more bugs than previous versions? Leopard was probably the most solid OS I can remember and once the 3rd party apps got on Board, Snow Leopard was even better.

With Lion, Mountain Lion and now Mavericks, there has been no end to the bugs...

Comments?

Actually, it's been a gradual regression... Snow Leopard was great, Lion had a few bugs but otherwise still impressive, and now Mavericks is the first contemporary Mac OS where I am actually afraid to install critical software updates. Sigh, I can't believe I was so foolish as to install 10.9.3 without doing a Time Machine backup first(?!).