MP 1,1-5,1 Apple LED Cinema Display - Black Screen

mechanize

macrumors newbie
Original poster
Jan 2, 2020
9
0
On Mac Pro startup or restart initially no display (black screen) on Apple LED Cinema 27 Display, have to unplug and plug monitor power socket every-time to make it works and it works fine until I switch off or restart the Mac Pro then I have to unplug and plug the power socket again to make it work !!!

Checked the Mac Pro with other monitor all works OK.
Any idea?
 

Snow Tiger

macrumors 6502
Dec 18, 2019
368
226
Have you tried to connect the display to another Mac with a mini displayport or displayport to mini displayport adapter to determine if its working fine ?
 

mechanize

macrumors newbie
Original poster
Jan 2, 2020
9
0
I have tried Mac Pro with different monitor and all works fine, I will now try cinema display with different Mac Pro and will post...
- - Post merged: - -

OK, I just tried Cinema Display with 2 other Mac Pros, 1 fitted with HD5870 cinema display showing same issue, but when I tried with Mac Pro which has nVidia GT120, it's working fine !!!
 
Last edited:

Snow Tiger

macrumors 6502
Dec 18, 2019
368
226
Connected to your original Mac , did your Cinema display work fine up until recently ?
 

Snow Tiger

macrumors 6502
Dec 18, 2019
368
226
Connect a different minidisplayport display to your original Mac Pro and determine if your graphics card is failing . If you don't have one available , then try a different interface capable display ( DVI ) . I assume you have a Mac Edition card .
 

mechanize

macrumors newbie
Original poster
Jan 2, 2020
9
0
Yes, all mac edition card and I already have tried (non apple) display port monitor (check my comments above) and that monitor is working fine with the MP, I also tried cinema display with other MP and with other MP cinema display is working fine !!!

I think Security Update 2019-007 is causing the problem !!!