Mid 2012 rMBP 15" and 4K, UHD, Samsung U28D590D Monitors

Discussion in 'MacBook Pro' started by iphone5att64, May 17, 2014.

  1. iphone5att64, May 17, 2014
    Last edited: May 17, 2014

    iphone5att64 macrumors 6502

    Sep 19, 2012
    We have a mid 2012 Retina MacBook Pro 15" and bought a pair of Samsung U28D590D UHD monitors.

    3840x2160 @ 30Hz is possible with the HDMI port. HiDPI and everything just works with 10.9.3. Everything did not just work with a mini-DisplayPort to HDMI adapter. 1920x1080 @ 60Hz was the highest resolution listed with the adapter.

    3840x2160 @ 30Hz is possible with the DisplayPort by adding a custom resolution with SwitchResX. Without SwitchResX, the highest resolution listed is 2560x1440 @ 60Hz and HiDPI scaling options are not enabled. We could not find the right setting to use HiDPI with SwitchResX.

    The monitors have a Picture by Picture feature. We tried to get 3840x2160 @ 60Hz by outputting 1920x2160 @ 60Hz from HDMI and DisplayPort. 1920x2160 @ 60Hz was possible with the DisplayPort. We could not set HDMI to 1920x2160. The monitor has one DisplayPort and two HDMI.
  2. jonisign macrumors regular

    Jul 7, 2007
    Very interested in this! I started a thread looking for a solution just like this–– let's move the conversation here. Some things to try:

    - Have you tried getting an active mini displayport to hdmi adapter? You might be able to run the second "panel" through that.
    - Did you try setting the resolution manually in switchresx for the HDMI signal?

    Hope you're able to get this working!
  3. iphone5att64 thread starter macrumors 6502

    Sep 19, 2012
    We tried an active HDMI 1.4 adapter tonight.

    3840x2160 @ 30Hz is possible with a DisplayPort 1.1 to HDMI 1.4 adapter. HiDPI works. 1920x2160 @ 60Hz is possible.

    3840x2160 @ 60Hz was possible with Picture by Picture outputting 1920x2160 @ 60Hz from mini-DisplayPort to DisplayPort and mini-DisplayPort to active HDMI 1.4.
  4. jonisign macrumors regular

    Jul 7, 2007
    Very cool! That's great to hear–– I have one of these monitors hopefully coming next week and am hopefully this method should work for the 2013 13-inch rMBP as well.

    Out of curiosity, you said that HiDPI works–– what settings do you get for your each of your 1920x2160 panels with HiDPI?

    Also, how does it look overall in 3840x2160 @ 60Hz?

    Finally, which active adapter did you use to get this working?

  5. iphone5att64 thread starter macrumors 6502

    Sep 19, 2012
    HiDPI wasn't enabled for 1920x2160 @ 60Hz.

    Accell DisplayPort 1.1 to HDMI 1.4 Active Adapter.
  6. iphone5att64 thread starter macrumors 6502

    Sep 19, 2012
    You will have to disable display has separate spaces for windows to span both outputs. That will set the menu bar on one display.. It will span half of the monitor if you use Picture by Picture.
  7. jonisign macrumors regular

    Jul 7, 2007
    Okay great, thanks for the update. To get HiDPI working, you could try creating a custom resolution for each panel in switchresx. For example, if you wanted to get the display to "look like" 2560x1440 OS X would normally create a 5120x2880 image and shrink it to fit on the 4K display. You might be able to split this up to get the right fits for 1920x2160?
  8. jonisign macrumors regular

    Jul 7, 2007
    Alright, I've got it working, however, I have a strange effect where the panel coming out of the HDMI port is much darker it seems than from the displayport... it's rather jarring. Did you have a similar experience? Any thoughts on this?
  9. iphone5att64 thread starter macrumors 6502

    Sep 19, 2012
    One panel was darker, but I thought it was because I lowered the brightness.

    Are you using a mini-DisplayPort to HDMI adapter?
  10. jonisign macrumors regular

    Jul 7, 2007
    I'm actually not using the adapter... just straight HDMI 1.4. I am able to get 1920x2160 @ 60Hz working just fine through the HDMI on a 2013 13-inch rMBP, so I figured I wouldn't need it. Were you ever able to get the brightnesses the same on the two sources?

    Also, I've been playing around with HiDPI but have had no luck so far... in switchresx it seems that there is an option for a 960x1080p which would effectively be a 1080p @ 60Hz HiDPI option... however it won't let me select it! Any luck on your end?
  11. iphone5att64 thread starter macrumors 6502

    Sep 19, 2012
    We're using 3840x2160 @ 30Hz on two monitors. We would have to use both Thunderbolt ports for 60Hz. We stopped trying for 60Hz with Picture by Picture.
  12. jonisign macrumors regular

    Jul 7, 2007
    So, I've been able to get 3840x2160 @ 51.75Hz over displayport working on a 13-inch 2013 rMBP and it looks fantastic, so I think I'll stick with this. The only thing is that I can't seem to get HiDPI working over 1080p. To get 51.75 Hz I just specified a custom resolution of 3840x2160 and used the max pixel clock I could get, which was 450 MHz. Maybe that would work for you? At nearly 52 Hz I find the refresh rate much more bearable than 30 Hz.

    Now, if only I could get HiDPI working above 1080p....
  13. sweeho macrumors newbie

    May 24, 2014
    Try this to enable hidpi mode http://cocoamanifest.net/articles/2013/01/turn-on-hidpi-retina-mode-on-an-ordinary-mac.html

    I have the monitor on-route. Plan to use the same picture by picture setup to get 60hz. I am using rMBP 15 2012.
  14. jonisign macrumors regular

    Jul 7, 2007
    Yeah, I've done this and have HiDPI enabled... unless Apple has green-lighted your model I don't think you're going to get a higher HiDPI resolution than 1080p on Intel graphics. However, maybe you'll be fine with nvidia?
  15. noratio macrumors newbie

    May 25, 2014
    Dual HDMI at 60hz

    I bought one Samsung U28D590D to test 4k on the bigger and it's stunning. I have a Macbook Retina 15 mid-2012 that is now on 10.9.3, so I have the scaled options.

    On HDMI with the built-in port on the Macbook, like you guys it's stuck at 30hz, but with the separated screen option over picture in picture with a resolution of 1920x2160 @ 60Hz.

    I than bought Mini Display to HDMI, so I would end up with two HDMI side by side (dual HDMI), but realized that this crappy adapter is limited to 1080p. So read your posts and saw that it requires an active adapter Mini Display port 1.1 to HDMI 1.4a that will support the 1920x2160 @ 60Hz. So I have ordered one from Amazon(Accell B086B-003B-2) and should have it somewhere this week. Having two HDMI is probably the best option to correct the brightness issue with mini-display port to display port (monitor-in) mixed with HDMI to HDMI(monitor-in).

    My questions is : will Mac OS will be able to see it as one big screen when I got both "side by side 1920x2160 @ 60Hz"?

    Because Windows 8.1 can no problem, it detects a surround screen in the physx NVIDIA panel options. I saw that Apple released lots of Multi Stream/side by side compatibility with other monitors and more recent Macbook Pro Reinata 2013 and up. But there is NO WAY I am going to spend another 3000$ on a Macbook knowing that Apple can, if they want, release a driver that can do what we are trying to achieve. Macbook 2012 has lots of horsepower to drive Multi Stream HDMI at 1920x2160 60Hz to equal the 4K at 60hz.

    Any tweaks with that program swithcresX and if so any tutorial on the clocking and HIDPI? Because actually at 4k 30hz, the scaled is fantastic, just laggy mouse and laggy screen that moves. I don't want to play game with this, so I don't care about this limitation, I want to edit webpages, some pictures (even if not IPS, this monitor has freaking nice color matching by setting the monitor in "standing mode" in the angle). I was really surprised!

    Also, I was really surprised by Windows 8.1 scaled correction and nvidia support for 4k. I have Final Cut on MacOS, other then that I would consider buying premiere for Windows if Apple doesn't release a proper driver for my Macbook that is compatible with my Samsung side by side HDMIs.

    Anyways, thanks for your help and hope we can push Apple to release some good drivers so we all enjoy 4k @60hz without having to buy another Macbook.
  16. sweeho macrumors newbie

    May 24, 2014
    Picture by Picture Half screen on HiDPI 1280x1440 60Hz

    I am using rMBP 2012 and just got my U28D590D. Managed to get 60Hz HiDPI working via HDMI on half of my screen using Picture by Picture Mode. Now I have to get the Active Mini Display port to HDMI converter to get the other half working. I am using SwitchResX.

    1. Set to Picture by Picture. You should now display at 1920x2160 6oHz.
    2. Open SwitchResX, go to U28D590 Tab, under Custom Resolutions, Add a new entry 'Scaled resolution' 2560 pixels 2800 Lines.
    3. File -> Save Setting. Restart Mac OS.
    4. After restart, the newly added Custom Resolution 2560x2880 should show as Active in Custom Resolution.
    5. Go to Current Resolution. You should have a new entry '2560x2800, 60 Hz (NTSC). Click on the Enabled in the Active Column, select "-> 1280x1440, 60Hz (NTSC)(HiDPI).
    6. File -> Save Setting. Restart Mac OS again.
    7. Open SwitchResX -> About SwitchResX and Launch Daemon.
    8. Point your mouse to 4K screen, right click, SwitchResX -> 1280x1440, 60Hz NTSC HiDPI.
    9. Now half your screen will be at 1280x1440 HiDPI!

    Good Luck.
  17. iphone5att64, May 26, 2014
    Last edited: May 26, 2014

    iphone5att64 thread starter macrumors 6502

    Sep 19, 2012
    3840x2160 @ 60Hz may be possible with HDMI 2.0.

    HDMI 2.0 is a protocol update meaning only updating software and firmware on 1.4 hardware is possible.



    The menu bar will display on half the monitor with Picture by Picture.

    Having horizontal Picture by Picture would be better to see the whole menu bar.

    We should contact Samsung for a firmware update to do this and HDMI 2.0.

  18. jonisign macrumors regular

    Jul 7, 2007
    This is excellent! Have you managed to get any of the other HiDPI modes working this way? For example, the other ones that apple seams to be approving for 4K displays are 3200 x 1800 and 3008x1692.


    Update... Just tried them and they work fine! Create panels of 3008x3384 and 3200x3600 for those options :)
  19. jonisign macrumors regular

    Jul 7, 2007
    Alright, so I finally have the Accell DisplayPort 1.1 to HDMI 1.4 Active adapter... while I'm able to get one half of the screen powered at 60Hz using my Mac's native display port, using the other half of the panel from the active DP to HDMI adapter is a horrible blurry mess. Any thoughts?


    Or, if I am able to get it working, the panel through the active DP to HDMI is shrunken so it only takes up a small portion of the screen rather than the whole half panel
  20. irock101 macrumors 6502


    Jul 26, 2011
    In the same boat. Just plugged my Retina MBP Late 2013 into the Samsung using a Mini DP to DP cable and the max resolution i get is 2560x1440 by default. No sign of anything higher or close to 4k. Disappointed to say the least..
  21. iphone5att64 thread starter macrumors 6502

    Sep 19, 2012
    Late 2013 should do 3840x2160 @ 60Hz over DisplayPort 1.2. Did you try using SwitchResX?
  22. irock101 macrumors 6502


    Jul 26, 2011
    Sorry just checked its early 2013. Doesn't work with Display port sadly.
    What settings should i use for switchRes? Its asking for hz etc.
  23. irock101 macrumors 6502


    Jul 26, 2011
    None of those resolutions work when using the display port on the early macbook pro retina.
    The 3008px resolution is the one i am trying to get to work as its the only usable one but cant work on it at 30hz. Trying to get it to work at 60hz but no luck. Either screen goes black or some extreme graphical errors occur.

    Attached Files:

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  24. iphone5att64 thread starter macrumors 6502

    Sep 19, 2012
    Try CVT-RB.

    This also worked for 3840 x 2160 @ 30Hz on DisplayPort.

    Front Porch 48 3
    Sync Width 32 5
    Back Porch 80 23
    Scan Rate Vertical 30Hz or 29.952Hz
    Positive Positive

    The pixel clock should become 262.50.
  25. irock101 macrumors 6502


    Jul 26, 2011
    Thanks but no luck :( Display just stays blank.
    Also 30hz is a no go. Would love to get the 3008px @60hz to work somehow.
    Looks fantastic on 30hz via HDMI but no love on the Display port.

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102 May 17, 2014