Q: monitor/display randomly go black for a few seconds
Hi, I'm experiencing the same issue with 2 different computers using different setups.
Basically, one of the two displays randomly goes black/blank for a few seconds, then comes back on.
- One is an iMac (27-inch, Late 2012), OS X Mavericks (10.9), 1TB Fusion, 24GB, 3.4GHz i7, 680MX with an external 24" LG Display atttached via Mini Displayport-to-DVI cable
- The other is an early 2013 15" Macbook Pro (Retina, 15-inch, Early 2013) OS X Mavericks (10.9), 256GB SSD, 16GB RAM with an external 27" Dell U2713HM display using Thunderbolt-to-dual-link DVI
On the iMac it happens on the iMac display, but not the external monitor, and on the MacBook Pro it happens on the external 27" monitor, not the laptop.
I'm 100% absolutely sure that my mouse is nowhere near the "hot-corner for display sleep" when it occurs. Besides, if that was the case both displays whould go black. It seems to have no relation to what apps are open or what I'm doing when it happens, except that I'm ususally moving the mouse at the time. I've tried letting go of the mouse and waiting to see if it continues to sleep, but no, it just turns on after 1-2 seconds. The Macbook hasn't had the issue when it's not using the external display.
I actually experienced this with Mountain Lion on the iMac too, but since both are using Mavericks now, and the issue is still there. I'm posting this in the Mavericks forum. Since it's happening on two considerably different systems and setups, I'm inclined to beleive it's a bug in OS X. Some posts have indicated that it may be caused by WindowServer crashing and restarting, but how can I tell? And if so, what the **** can I do? Anybody else experienced this?
What I have tried:
Disable display sleep hot corner
What I haven't tried yet:
Unplug external display on iMac to see if it still happens (this cannot be tested on the laptop since only the external display goes black)
In both cases I'm using some type of USB 3.0 hub - the iMac has the 7-port Satechi USB 3.0 hub (lovely) and the Macbook is using the Dell monitor's built-in USB hub.
iMac (27-inch, Late 2012), OS X Mountain Lion (10.8.2), 1TB Fusion, 8GB, 3.4GHz i7, 680MX
Posted on Nov 22, 2013 5:26 AM
I just had the same problem with our Dell U2715H and DisplayPort-to-miniDisplayPort.
I could solve it by enabling DP 1.2 (DisplayPort version 1.2) in the monitor settings.
It seems like a lesser version can't handle the resolution of 2560x1440 so well (because the bandwidth is too low).
Posted on Dec 17, 2015 8:02 AM