MP 6,1 Mac Pro 6,1 - 12core /D700 flicker issue

chriskuta

macrumors newbie
Jan 16, 2020
10
1
Sydney Australia
I'm so glad I found this thread! I have exactly the same issue (the screen capture above is EXACTLY the same as mine).

MacPro6,1 - 3.5 GHz 6-Core Intel Xeon E5 - AMD FirePro D500 3 GB MacOS 10.15.2

Had the Trashcan Mac Pro since new on a 2k display and recently moved to a new Dell 4k display U2718Q and this is when I first started noticing the problem. Connected via Thunderbolt to DisplayPort.

Observations
1/ Only happens when I used Scaled graphics mode (worst at looks like 2560x1440) Default for display is rock solid (weird).
2/ Chrome makes the problem show itself more regularly, even to the point of when its happening closing Chrome and opening the very same website in Safari its fine. (again so weird..)
3/ Benchmarked/stressed the GPU using Valley and runs fine (can't get 4k resolutions in Valley though). But no problems with cooling / temps etc.
4/ My HDMI port doesn't seem to work, I can't get a picture on any monitor here. Nothing. I'll have to try an LCD TV.
5/ System Report - is showingResolution: 5120 x 2880 (5K/UHD+ - Ultra High Definition Plus) UI Looks like:2560 x 1440 @ 60 Hz but its a 4k display.. Is this somehow related to timing?

Things I've tried

1/ Cleaned the case of dust and replaced the GPUs thermal paste. (no change)
2/ Running Macs Fan Control I tweaked the fan so it speeds up faster at lower GPU temp settings. (no change)
3/ Clearing the NVRAM over and over and over... (no change)

Things I want to try
1/ Plugin two monitors to see if the other GPU / Monitor has the same problem (don't have a 2nd 4k monitor)
2/ Remove one of GPUs (can this be done). I have heard of Wattage Ceiling problems in Mac Pro perhaps its a power demand / supply issue?
3/ Turn it into a real Trashcan and forget about it.. ;)

Chris
 

th0masp

macrumors 6502
Mar 16, 2015
410
210
germany
So this crazy flickering is something that only shows up in certain apps while running on a 4k display? I have not seen this at all on mine with my main screen being a 1440p display but also ocasionally running a 4K TV as a secondary at its native resolution, both hooked up via TB.

I have never installed Chrome on this machine though, nor do I use Safari.
 

daveedjackson

macrumors regular
Original poster
Aug 6, 2009
169
143
London
For me it has nothing to do with scaled res or default. Nothing do do with software. It’s there as soon as I move the mouse.
 

chriskuta

macrumors newbie
Jan 16, 2020
10
1
Sydney Australia
@daveedjackson - oh geez that's is a lot worse than mine then.

As @w4rmk mentioned above, I also agree, on mine the glitch is still always there but its very hard to notice, just the odd white line here and there mostly on the right of the screen. Interacting with elements on-screen (especially moving the pointer over something) causes the major flickering & screen corruption.

I'll run mine in default resolution (full 4k no scaling) for a while and see if I notice anything since I'm pretty sure this resolution is problem free for me.

I'm no expert here, but seen enough graphic cards problems to surmise that I don't think its a graphics card memory problem, nor a temperature problem, I actually don't even think its graphics card since it never faults under hard benchmarking. My gut feeling is that is a buggy driver issue or maybe a weird timing issue.

I've haven't been able to force 50Hz refresh rate, I've tried a bunch of commands from brew and also SwitchResX but nothing works always stuck on 60Hz. If I could try 50Hz and see it still glitch I think the timing issue could almost be ruled out. I'll try 30Hz for a while and check that.. and get back to you all.
- - Post merged: - -

I am going to perform a test and run with only 1 graphics card connected and try each card individually to see if one is failing and one is not.
@w4rmk how did this end up? I wasn't aware you could do this. Doesn't only one of the GPU boards have the M2 drive port?.. I'd be happy to try this just don't want to fry anything :)
 
Last edited:

yurc

macrumors regular
Aug 12, 2016
181
87
inside your DSDT
Some trashcan model manufactured between 2015 February - April production have affected GPU problem and should be eligible for replacement if I recall. This is only for D500/D700 only, D300 was not affected.

edit @ astrorider already mentioned it.
 

w4rmk

macrumors 6502
Feb 13, 2006
273
68
Sorry I didn't end up trying the single graphics card option. My frustration with the D700 reached the point of no return and I gave up on the D700 trashcan, nothing I tried would completely alleviate the flickering with a 4k display (and I tested with different 4k displays). I ended up selling it and I am keeping my D300 which works great at 4k and I've not had any display issues. I also had noticed that the D700 ran hotter than the D300 and I really don't need high-end graphics (use it mainly for office tasks). I just lost all confidence in the D700 trashcan and had no more interest in battling it out with Apple.
 

chriskuta

macrumors newbie
Jan 16, 2020
10
1
Sydney Australia
Thanks for the reply. Sounds like a good plan :) Mine is a late 2013 so not part of that recall.

Out of interest are we all on Catalina? Or is Mojave the same?
 

chkwong

macrumors newbie
Jan 17, 2020
25
5
hi all
I have same problem with Mac Pro 2013 12 cores D700 with right screen flicker. I am using LG 5K ultrafine with default resolution 2560 x 1440 scaled to 5120 x 2880 at 60Hz. Connection through thunderbolt 2 to 3 adaptor.

I have tried to downgrade macOS to

Mojave: still have flicker
High Sierra: no flicker


I have tried to use the same resolution with 30Hz with SwitchResX, then there is no flicker.
If I airplay to Apple TV, flicker gone too.

I think it is a driver problem.


I have another Mac Pro 2013 12 cores D300: no flicker

I would like to know if D500 have similar flicker problem here?
- - Post merged: - -

Windows 10 bootcamp using 3840 x 2160, no flicker
 
Last edited:

chriskuta

macrumors newbie
Jan 16, 2020
10
1
Sydney Australia
Just confirming that I've run mine at 30Hz for about an hour and haven't notice anything. But this isn't a solution -- feels like like you're stuck in some sort of oozing mud.. :)
 

w4rmk

macrumors 6502
Feb 13, 2006
273
68
Downgrading to a lower res (2.5k) display is another option. I only had issues with 4k displays.
 
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chriskuta

macrumors newbie
Jan 16, 2020
10
1
Sydney Australia
One of the items in the report (chkwong posted above) mentions coming out of sleep mode. I've reboot my machine and basically turned sleep off (display sleep) and so far so good.. WTF.. I'll keep testing..
 

chkwong

macrumors newbie
Jan 17, 2020
25
5
One of the items in the report (chkwong posted above) mentions coming out of sleep mode. I've reboot my machine and basically turned sleep off (display sleep) and so far so good.. WTF.. I'll keep testing..
Can u use 4K or 5k at 60hz in Catalina after turning sleep off without flicker?
 

chkwong

macrumors newbie
Jan 17, 2020
25
5
One of the items in the report (chkwong posted above) mentions coming out of sleep mode. I've reboot my machine and basically turned sleep off (display sleep) and so far so good.. WTF.. I'll keep testing..
Still have Flicker when using 4K or 5k at 60hz even turn sleeping off
 

CC88

macrumors regular
Sep 29, 2010
238
32
Can you please try to connect your monitor both on DisplayPort and HDMI if the monitor has both?

So: one display port cable out of macpro to the monitor. One hdmi cable out of macpro to the hdmi monitor port.

Than use display port on the monitor. Hope all is clear. Let me know.
 

chriskuta

macrumors newbie
Jan 16, 2020
10
1
Sydney Australia
Maybe a false alarm as I think I was in 30Hz and I didn't realise it. I've put it back to 60hz and we'll see..

I don't get flicker or glitches all the time (4k looks like 2560x1440 @ 60Hz) it really just comes out of nowhere and just gets worse when I move the mouse around. Seems to be related to how much is on screen, like playing YouTube and having Spotify open etc.. But Google Docs in Chrome makes it go crazy fairly consistently..
 

CC88

macrumors regular
Sep 29, 2010
238
32
Maybe a false alarm as I think I was in 30Hz and I didn't realise it. I've put it back to 60hz and we'll see..

I don't get flicker or glitches all the time (4k looks like 2560x1440 @ 60Hz) it really just comes out of nowhere and just gets worse when I move the mouse around. Seems to be related to how much is on screen, like playing YouTube and having Spotify open etc.. But Google Docs in Chrome makes it go crazy fairly consistently..
Please try to connect both display port and hdmi port. Than use the monitor on the display port and let me know. It will recognize two interface connected but you can use only the Dp. Try and report back.
 

chkwong

macrumors newbie
Jan 17, 2020
25
5
Please try to connect both display port and hdmi port. Than use the monitor on the display port and let me know. It will recognize two interface connected but you can use only the Dp. Try and report back.
My LG 5k only has one thunderbolt input

is there a method to fake a second display in MacOS?
- - Post merged: - -

If I airplay to Apple TV or Sidecar to ipad

the flicker problem is gone and could use 4k or 5k at 60hz without problem
 

CC88

macrumors regular
Sep 29, 2010
238
32
My LG 5k only has one thunderbolt input

is there a method to fake a second display in MacOS?
You can try something like Airplay if you have an appletv.

I say this because I got strange issue with my trashcan and D700 using a 60Hz monitor. But no if I used Airplay projecting my monitor on a TV via aTV.

Then, after connectng my monitor both in dp and hdmi I solved any glitch issue. Maybe the gpu solve some frequency issue using both input ot Airplay. Don't know why, but it's not a problem that apple is aware of.

See post below by me:

 

chkwong

macrumors newbie
Jan 17, 2020
25
5
You can try something like Airplay if you have an appletv.

I say this because I got strange issue with my trashcan and D700 using a 60Hz monitor. But no if I used Airplay projecting my monitor on a TV via aTV.

Then, after connectng my monitor both in dp and hdmi I solved any glitch issue. Maybe the gpu solve some frequency issue using both input ot Airplay. Don't know why, but it's not a problem that apple is aware of.

See post below by me:


Thanks for information
Yes I use airplay to Apple TV, then no flicker at 60 Hz

but still want to find a better solution for this
 

CC88

macrumors regular
Sep 29, 2010
238
32
Thanks for information
Yes I use airplay to Apple TV, then no flicker at 60 Hz

but still want to find a better solution for this
I didn't find a solution other than connecting my LG 32" monitor both in dp and hdmi. It's a nice solution in my case. The system see two monitors I configured in duplicate mode. So I can use my monitor via DP without flicker.

I have tried switchresx, and many other setting without luck.

Maybe with the hdmi attached or during airplay the gpu change a little in frequency and it work fine.

I can't tell how to solve the problem in your case... The only solution is to have a monitor with both dp and hdmi and use both input at the same time.
 

chkwong

macrumors newbie
Jan 17, 2020
25
5
I didn't find a solution other than connecting my LG 32" monitor both in dp and hdmi. It's a nice solution in my case. The system see two monitors I configured in duplicate mode. So I can use my monitor via DP without flicker.

I have tried switchresx, and many other setting without luck.

Maybe with the hdmi attached or during airplay the gpu change a little in frequency and it work fine.

I can't tell how to solve the problem in your case... The only solution is to have a monitor with both dp and hdmi and use both input at the same time.

Thanks for info

I am using @30Hz by SwitchResX to avoid flicker
 

sparkplug37

macrumors newbie
Jul 30, 2010
10
4
FYI, I have a Mac Pro 6 core connected to a Dell 5k monitor (two DP) and I get a flicker on the right hand side of the screen when I do any intense hard drive activity. So if I test the drive speed I get lots of flickering and at idle very little. Using a scaled screen mode gave more flickering but the default half res did not stop it completely.

I too went to Apple to complain and they did replace my graphics card but I still got the issue. I then contacted Apple Care and got the run around for several month to be told they can see something but it might be fitted in an OS update in the future and good bye. Later I did find that some beta versions of Mac OS did not flicker, so I suspect a graphics driver issue.

Since then I have replaced the CPU to a 10 core and replaced the hard drive to a Samsung NVME drive and it still flickers.

In the end I fitted an external graphics card (Radeon VII) and I now get no flicker.