9600x1080 : framerate issues

edited April 2014 in MAIN
Hello everybody,

I have a setup with six 1920x1080 outputs.
No videos playing, just internal test pattern.

As far as I use four outputs with 7680x1080 resolution, the framerate stays at 30fps.
Enlarging the resoltion to 9600x1080 (5 screens) or more, the framerate drops to 20fps.
I can split the 7680x1080 resolution on 6 screens -> framerate is 30fps.

What does the global framerate do exactly?
I set it to 60fps, when fullscreen is activated it drops to 30fps/20fps (depending on total resolution as described above)??
Exiting fullscreen it goes to 60fps again...

Preferences: 64bit mode, 24GB memory usage.

System: dual 8-Core-Xeon, 2x GTX760, 64GB RAM, Mavericks 10.9.2



  • edited April 2014
    Hello @rolandino,

    As explained in this post, it's better to use outputs from the same graphic card : computations between multiple graphic cards take additional time (this problem is hardware, and other softwares have the same issue). Of course, it's only visible when going fullscreen.

    However, we recently worked to optimize multi-GPU support : be sure to try this beta version, and please post your comments.

    Thank you. Philippe

    PS : global framerate is just the "maximum framerate", and should not be changed in your case
  • Hi 

    I've been looking in to this kind of issue to and doing some tests for Philippe. 

    Looks like its the way that the Nvidia cards handle the screens and the OpenGL Windows or Mac. Philippe has put together quite a few versions of Millumin to test the multiple card performance .
    In the forum posts in the lab section there is a topic devoted to this and downloads of 2 different Millumin's which use different ways of handling the frame buffer. 

    1.47L works best for me at 9600 x 1080. It gives 60fps across all with live inputs. Give them a try. Would be interested in your results.

    OpenGl monitor driver in the developer tools for mac should give you a bit more detail on what the cards are doing . If it's a Hackintosh then the hardware monitor from the SMC kext should also show the GPU and Mem Frequencies.You could also try disabling Beam Sync (Mac's version of Vsync) but this may give tearing.

  • Ok, thanks... I will try the beta version later and let you know...

    Just two more notices:
    - It seem's like, that it does not depend on using outputs from only one or both gfx cards.
    When I use four screens with 7680x1080, two outputs on the first card, the other two on the second, I get 30fps, everything fine.
    - I made a quick check on my MacbookPro Retina too. As soon as the screen size exceeds 7680x1080, framerate is dropping when entering full screen (again no videos playing, just test pattern, all screens same output).

  • Hello @rolandino,

    No, it depends on using outputs from the same graphic card or not : the max framerate is 60fps, not 30fps.
    Moreover, your test on your MBP Retina is very strange : please have a look to this benchmark at 7680x1080 with 3 movies of the same size (~45fps).

    Did you test without the test pattern ?

    Best. Philippe
  • Hello again,

    coming back with some test results with different setups:

    1. 5760x1080, 3 screens
    1a. only one gfx card: 60fps on all versions (1.48, 1.47m, 1.47l)
    1b. Millumin user interface on gfx card 1, all screens on gfx card 2: 30fps on all versions
    1c. user interface an screens mixed on both gfx cards: 30fps on 1.48 and 1.47l
         interesting 1.47m: on gfx card 1 (that with the user interface) 40fps, on gfx card 2 20fps

    2. 7680x1080, 4 screens
    2a. Millumin on gfx 1, all screens gfx 2: 1.48 > 30fps, 1.47l and 1.47m > 20fps
    2b. user interface and screens mixed on both gfx: 1.48 > 30fps, 1.47l > 20fps
          again special results on 1.47m: about 30fps on gfx 1, about 20fps on gfx 2

    3. 9600x1080, 5 screens
    1.48 > 20fps, 1.47l and 1.47m lower than 20fps

    and once again one thing on 1.48:
    7680x1080, 4 screens -> 30fps
    as soon as I open output setup and enter something above 7680, e.g. 7800, framerate drops instantly from 30 to 20 fps and stays there.

    I did not try the Nvidia web drivers. any experiences with them anybody?

    Anything else I could try?

    Attached is a screen shot from OpenGL extensions viewer...

    Hope my tests help doing improvements...


  • Only a Guess but have you tried moving your second GFX card to a different slot. Some of the dual cpu motherboards have PCIE lanes controlled by each Cpu. Looks like your system should have 80 pcie lanes, 40 off each cpu , If your GFX cards are on different chip lanes maybe this could cause some issues.Could be worth trying.

    I'm running lga2011 single cpu, The frame rates across my gtx660's is between 58-60 on all screens up to 6 outputs across multiple cards. 

  • Actually that came to my mind also already, though I haven't tried yet. But you're right, the cards are on lanes from both CPUs right now. I will make a test next week and let you know.

    Also made some tweakings with Apple graphics power management lately. the first card runs at 1,08 GHz, the second only 680 MHz, obviously one P-state lower. Perhaps you ran across this issue too, didn't you? Do you have a link or something for me? Found a lot about that kext stuff, but not sure, if I adjusted everything correct in AGPM.kext.

  • Hi 

    I found that the AGPM on the gtx 660's works fine. Both cards ramp up to 1.47ghz Mem and 1.08GHZ on Clock.
    Different versions of Millumin i used showed different clock speeds on the second card. 1.47L game me full Clock on both cards. The AGPM is also related to the SMBIOS you use so maybe the MP 6.1 is not doing everything you need. 

    Don't want to turn this in to a Hackintosh forum for the sake of other users so P.M me and we could go through results then share the conclusions with other users.


  • Yup, I'll send you a P.M. to discuss the hackintosh stuff...

  • Hello @rolandino,

    Let me know the result of your tests.
    Also, check that your outputs are not locked at some low frequency : when going fullscreen, Millumin will synchronize itself at the lowest frequency from the outputs.
    Such low frequencies can happen with multiscreen cards such as TripleHead or Datapath X4.

    Best. Philippe
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