Using OS X 10.11.3, Mac Pro 5,1, 32GB RAM, Radeon HD 7950 (Sapphire) graphics card w/ 3GB VRAM. I have a multiple monitor setup with displays not having separate Spaces. Usually, when using a shortcut key to change spaces, I see a nice animation where one space slides to the left, and the new space slides in from the right.

However, once I have around six "desktops" and/or a certain number (unknown) of windows open, the animation displays a black screen when sliding the new space into place. Happens in both "directions" - the current space slides left/right, and the black screen slides in. Once the changing of the space is complete, the black goes away and the desktop reappears. This video shows the phenomena at 0:15s.

Anyone encounter this and find out why this might be occurring? Never happened with the same hardware using OS X versions prior to 10.10.

  • A guess would be your GPU is running out of memory to be able to recalculate the transition, so it gives up & just draws once the transition is complete. Knowing what Mac & graphics would help.
    – Tetsujin
    Feb 11, 2016 at 19:53
  • Thanks @Tetsujin, I have added some specs. I too was suspecting something either graphics card or OS related to the buffer for this animation, but I have never witnessed this with versions of OSX prior to 10.10.
    – ybakos
    Feb 11, 2016 at 20:47
  • hmm, OK, pretty much the same as my rig - can't say it's something I've seen. 2nd guess would be RAM struggling, trading to HD. I do see some occasional slowdown on this machine even with SSD boot drive & 64GB RAM. I'd blame Safari if I had a single vague culprit; haven't managed to find a cure though mine doesn't go so far as a black screen, it does sometimes judder across. Second swap is fine, just first is slow if i've been in one Space a long time.
    – Tetsujin
    Feb 11, 2016 at 20:51

2 Answers 2


It is not a GPU issue. enter image description hereWith OS X 10.11, this can be corrected by turning Dashboard off or setting it as an overlay (System Preferences>Mission Control).

  • I disagree. I have always used Dashboard as an overlay (the classic style). Thanks for the suggestion, though.
    – ybakos
    Aug 26, 2016 at 14:22

Had that same issue because I had ScreenShade installed. Disable it, if you have it installed, and the problem will stop.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .