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MP 6,1 Mac Pro 6,1 - 12core /D700 flicker issue
- Thread starter daveedjackson
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I know but after using my monitor @30Hz before I found the solution I wanted to change my macpro and buying a macmini with eGPU. It's unusable for me.
The solution is using an Airplay connected device to project or a monitor that support also HDMI and attaching two video output cable to the macpro and using only dp to have no flicker at all because HDMI on macpro is @30Hz.
Mac Pro is still worth to keep. Xeon CPU, ECC ram, elegant design
the Mac Pro could use egpu too by purge-wrangler script
I have the Dell 5K and the Mac Pro. These issues are almost always the result of somewhat poor pre-emphasis negotiation by the display controller and lower quality cabling. The upshot is that you should use the shortest and highest quality displayport cables that you can. You should also ensure that there is not additional cabling or other sources of interference around.
@chkwong are you saying that having a second monitor in any port (or only HDMI) has stoped the issue?
I'm at a loss since my HDMI port either doesn't work anymore or doesn't like my two monitors here, but I can connect a second monitor via a second DP to HDMI. Given your understanding of the problem should this work too? Or does it have to be the same resolution / sync?
@sparkplug37 interesting about the HD activity I'll have to try a speed test on mine as well..
I'm at a loss since my HDMI port either doesn't work anymore or doesn't like my two monitors here, but I can connect a second monitor via a second DP to HDMI. Given your understanding of the problem should this work too? Or does it have to be the same resolution / sync?
@sparkplug37 interesting about the HD activity I'll have to try a speed test on mine as well..
Second monitor may stop the flicker
I tried airplay and Sidecar, both can stop flicker
haven’t tried second monitor through HDMI or DisplayPort
good to know that
my LG 5k only has one input ...I am thinking is there any method to fake a second display in macOS?
Hey, I'm saying that you can attach the same monitor with dp and hdmi to the macpro using two cables. And the issue stop.
If you don't have an hdmi on your monitor you can try to use airplay to project your monitor to another source and check if the issue stop.
You have to use the hdmi port on the macpro. Using two dp is not a solution in my case.
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Can you share amazon link so in the case I can eliminate the hdmi cable from macpro to monitor?
EDIT: https://www.amazon.it/EasyDiy-Emula...signal+dummy&qid=1579602058&sr=8-1-fkmr1&th=1
Maybe I can give it a try to see if I can remove my hdmi cable.
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Yes , it is the HDMI signal dummy
Look forward to your test
airplay is not good solution as every time Mac Pro go to sleep, need to reconnect airplay again
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Airplay is a short term solution... But it was the thing that helped me finding the hdmi solution.
Will try if I can have the hdmi dummy in short time and in case get it back to amazon if it doesn't work.
EDIT: ok the hdmi dummy will be here tomorrow, I will let you know.
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Great !
Strange that high Sierra no such flicker problem
Did anyone report to Apple about this flicker problem in Catalina already ?
I have it both in Mojave and Catalina. Starting with mojave. HS no flicker at all. I don't know why.
If you use only the dp cable with macOS you have the flicker. But, if you start a Virtual Machine in VmWare Fusion you don't have the flicker in the VM but you have in macOS.
I was dealing with it from Mojave's launch and finally the only solution found was to add the hdmi cable. Maybe the dummy hdmi will be a solution too.
I think the issue is related to gpu slot 2 . and it is related to Metal API.
stressing it with Geekbench 5 with compute api metal testing gpu slot 2, the flicker is gone during the test.
The MP 2013 bad graphics card flickering is usually fairly evenly distributed around the screen and also usually involves the screen going briefly completely dark. The flickering that happens on just the right edge of the screen with 4K displays is sometimes a bad DisplayPort cable or a cable with insufficient bandwidth (not certified as DisplayPort 1.2 or better). This used to be very common a few years back when 4K displays were first becoming popular and even the cables included with the monitors had issues.
just tried two different apple thunderbolt cable , 50cm and 2m
Still have right edge screen flicker
I've been using a second monitor for a few days now (its an older 4:3 Dell 2007FP) connected via DP > HDMI > DVI. Running at 1600x1200 @60Hz - remember that rez? 
I've not had any issues, no flickering or lines or flashes. Confirming that the primary monitor (Dell U2718Q) is running at 3840x2160@60Hz (scaled looks like 2560x1440).
I've not had any issues, no flickering or lines or flashes. Confirming that the primary monitor (Dell U2718Q) is running at 3840x2160@60Hz (scaled looks like 2560x1440).
I've been using a second monitor for a few days now (its an older 4:3 Dell 2007FP) connected via DP > HDMI > DVI. Running at 1600x1200 @60Hz - remember that rez?
I've not had any issues, no flickering or lines or flashes. Confirming that the primary monitor (Dell U2718Q) is running at 3840x2160@60Hz (scaled looks like 2560x1440).
next is to try HDMI dummy dongle
The original one is Newertech HDMI headless.
There is also cheaper dongle made by China.
Mine had to be here on wednesday but amazon has a delay in shipment. Maybe today or monday I can tell how does a dummy hdmi work for the macpro.
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It's not the cable. The only solution is to have to output one from dp and one from hdmi for no flickering @60hz.
I tried five different monitors, three different cables etc. The only solution found was to output on both hdmi and dp. Luckily my monitor has both.
this one seeems to be better built and support macOS
NewerTech HDMI Headless Video Accelerator (HDMI Dummy Plug), 4K Display Emulator up to 4096 x 2160 Ultra High Definition Resolution
Harness the power of your Mac's GPU when accessing your Mac remotely using the HDMI headless video accelerator for remote access of select Apple Mac Mini from NewerTech. This discrete HDMI adapter plugs into your Mac's HDMI port and activates the GPU to emulate displays up to 1080p when accessing...
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I have tried your solution with success
One thunderbolt output to LG 5k
and one HDMI output to old monitor
no flicker at 60hz then
the old monitor does not need to be power on. even if HDMI connected to old monitor switched off, Macos still recognises the second display
i think HDMI dummy should be a success too