2016 Macbook Pro and Dell UP2715K 5K Display MST

Discussion in 'MacBook Pro' started by Cobratom, Nov 20, 2016.

  1. Cobratom macrumors newbie

    Nov 20, 2016
    Has anyone else tried the Dell UP2715K 5K monitor?

    I have a 2016 Macbook Pro 15" with the AMD 460, and I can't seem to get it to work. I ordered a couple of USB-C to displayport adapters and it works fine in single stream and I can show 4K without issue. However it will not give me an option or even recognize the second adapter/cable so there is no way to get 5K to work.

    Any ideas?

    Thank you!
  2. adeblas macrumors newbie

    Nov 28, 2013
    Please post if you get it to work.
    I just have bought a refurb 2015 rbmp and just bought this monitor on sale for around $700. As any monitor usually lasts 3-4 computers I am concerned I will have problems in the future.

    By the way a maxed out 2015 Rmbp + this monitor was the same price as the equivalent 2016 model.
  3. symphara macrumors 6502a

    Nov 21, 2013
    I imagine you need one USB-C to dual-DisplayPort adapter, not two USB-C to single DisplayPort adapters.

    I've only seen one such thing online and it specifically advertises 5k support but I have no idea if it actually works.
  4. hiker- macrumors newbie

    Nov 6, 2016
  5. adeblas macrumors newbie

    Nov 28, 2013
    I don't see the reason why it doesnt work.
    By the way how is 4k on this native 5k display?
  6. symphara, Nov 21, 2016
    Last edited: Nov 21, 2016

    symphara macrumors 6502a

    Nov 21, 2013
    It's great, no fuzziness at all. Pin sharp.

    PS: in Windows 10, with my desktop machine. My Macbook is too old to drive this monitor.
  7. wilsonjchan macrumors newbie

    Sep 20, 2013
    I got my 2016 15" MBP w/TB to work with my Dell UP2715K today. Using 2 Accell USB-C to Displayport cables, I was able to get full 5K but I did have to struggle a bit with SwitchResX, the Display setting, switching the monitor between 4K and 5K, and power-cycling it a few times to get it to work. It's been working fine for 7 hours now. I'm hoping to get either a dock or a dongle that has USB-C to dual Displayport MST to reduce the clutter.
  8. janus19 macrumors newbie

    Sep 17, 2009
    Does sound work through the display?
  9. mulvone19 macrumors newbie

    Oct 12, 2015
    Cincinnati, Ohio
    I have yet to get the sound to work with my display. Only works with SST 4k. Other than that monitor works fine with 5k. I use two USB C to DisplayPort cables by J5.
  10. rocker82 macrumors newbie

    Dec 15, 2016
    So anyone else have any experience getting this to work? I have it working - kinda...

    2016 15" MBP with Radeon Pro 450
    Dell 27" 5K Monitor (UP2715K)
    2x CableMatters USB Type-C to DisplayPort Adapters (from Amazon)

    Note the Dell UP2715K had been connected to my Late 2015 Retina iMac 27" for a while with zero issues. The display is flawless and perfect. Connection was done using the Dell-included dual thunderbolt to mDP cables.

    1st Attempt

    Monitor had been in power saver mode. Same with the MBP. Used Dell-included dual DisplayPort to DisplayPort cables (different from what I had been using for my iMac). Used the CableMatters USB-C to DP adapters. Plugged in the blue marked cable first. Then the other one. Used the two left side USB-C ports on the MBP. Dell came to life but the resolution was capped at 2560x1440 on the UP2715K. No matter what I did, it wouldn't go into 5K. Tried all the USB-C ports on the MBP but didn't work.

    2nd Attempt

    Opened the Energy Saver control panel and forced the MBP to always use the high performance graphics. Tried a bunch of things but the UP2715K was stuck at 2560x1440.

    3rd Attempt

    Rebooted the MBP and also pulled the plug out of the UP2715K, waited a few seconds, and then plugged power back in. Waited for the MBP to fully come up. This time it worked. 5K. The Display control panel gave me the Scale options for the UP2715K as well. Great! ... err so I thought. After about 5 minutes, I started seeing some shaking, but only in the lower right quadrant of the UP2715K. If you split the UP2715K into four equal size pieces, it's the lower right one that was shaking for me. It was shaking in the horizontal direction. At first it would shake once every 20-30 seconds. Then it became more frequent. Until finally it was shaking once every couple seconds ago. No good. Tried rebooting again a few times. Display always came back in 5K but the jittering was still there. Tried all the Scale options, no help. Tried unplugging the USB-C power cable. No change. I have a USB-C dongle going to an external keyboard. Tried unplugging that. No change. Ugh.

    4th Attempt

    Decided to try different combinations of USB-C ports on the MBP. The one that seems to "work" is if I don't put both cables on the same side of the MBP. So now I have one (the blue marked one) on the rear right port of the MBP. And I have one on the rear left port of the MBP. The power cable is on the front right port. And my keyboard is on a dongle on the front left port. So far, no more shaking. It's been stable for the past couple hours. Knock on wood.


    It could be pure coincidence that I'm not getting the shaking right now. I won't know until a few more days go by at the minimum. But if keeping the cables away from each other does indeed help, I'm guessing it's noise related? or maybe some type of throughput issue? Could be the adapters I'm using? Or maybe it's just a bug in the OS? As someone pointed out, Apple's latest resolution doc seems to have removed the Late 2016 MBP from supporting the dual cable approach to 5K. I swear it was listed there before but now only the iMac/MacPro are.

    Would be great if other people who've gotten it working could post which adapters they purchased.
    --- Post Merged, Dec 15, 2016 ---
    Oh, and I forgot to mention. Sound works perfectly for me. I have the sound menu bar icon enabled and it shows that audio is being redirected to the UP2715K. And I can hear the audio loud and clear coming out from the UP2715K. The audio has been flawless for me.
  11. mulvone19 macrumors newbie

    Oct 12, 2015
    Cincinnati, Ohio
    I used star techs USB C To MDP cables to avoid adapter issues. Everything is relatively smooth except I cannot get audio out of it. Also my mouse will lag sometimes when the monitor wakes and requires a reboot on the monitor. Will also have some issues where the cursor will freeze on the screen or duplicate. Something with macOS and 5k support. I really wanted the monitor to work because it's got a great finish to it but it's been finicky as of late plus who knows when a working thunderbolt 3 dock will be available for it. Going ahead and just getting the LG 5K display when it's available.
  12. AdonisSMU macrumors 604

    Oct 23, 2010
    Amazing! really sharp display.
  13. rocker82 macrumors newbie

    Dec 15, 2016
    24hrs later, flickering isn't there. But sleeping is causing problems. It wakes up stuck in the wrong resolution. Need to pull the plug on the monitor, wait a few seconds, plug back in to get the right resolution back. :/
  14. AppleSmack macrumors regular

    Jun 30, 2010
    After waking the MBP from sleep, can you just use the power switch on the monitor to turn it off/on? Or does it only work if you pull the plug?
  15. kinster macrumors 65816


    Nov 6, 2006
    Obviously last seasons will always be cheaper.
  16. rocker82 macrumors newbie

    Dec 15, 2016
    Well when it happened yesterday, using the power switch to power cycle the monitor and also unplugging/plugging the display cables didn't help. I had to pull the power cable on the monitor to get it back to normal resolution.

    This morning, I brought it out of sleep and everything was fine. And still no more flickering.
  17. AppleSmack macrumors regular

    Jun 30, 2010
    Thanks for the update, rocker.

    If Apple don't sell the LG 5k at December discount pricing, the Dell 5k you have is my backup plan (and longer term, the connectivity options on the Dell are far better).

    Please can you update us in the next week or so what proportion of wake ups require you to pull the power (deal breaker!), vs waking up with no problems (yay!). Good luck with it :)
  18. rocker82 macrumors newbie

    Dec 15, 2016
    Will do.
  19. rocker82 macrumors newbie

    Dec 15, 2016
    So I'm seeing about 40% bad wrong resolution wake ups (2 out of 5).

    But did notice one thing. I have an external keyboard plugged into the MBP via USB-C to USB dongle. And I have a Bluetooth Magic Trackpad 2. The two times I had a bad wake up, I woke up the MBP via the external USB attached keyboard. The three times I had a good wake up, I woke up the MBP by clicking on the Magic Trackpad 2.

    Not enough data points yet though.

    There's multiple threads about sleep wake up issues on the new MBP so no telling if all my issues are caused by some incompatibility between the new MBPs and the UP2715K or if it's caused by the general sleep issues people are having.
  20. AppleSmack macrumors regular

    Jun 30, 2010
    Hmm, interesting. If all it takes for consistent good wake-ups is waking with the external mouse rather than the keyboard, this could be promising.
  21. rocker82 macrumors newbie

    Dec 15, 2016
    Ok so that wasn't it. Happened with waking via trackpad too. I'm at about 50% with resolution issues on wake. And one of the quadrants on the monitor started shaking again. But maybe once every hour or something, not nearly as frequent as before.

    So I can't recommend this setup right now unless you're willing to accept the glitches from time to time.

    For the most part it works at 5K and it's super sharp and clear. But the random corner of the display shaking from time to time and the messed up resolution on wake from sleep about 50% of the time is annoying.

    Unclear whether it's caused by the various graphics glitches on the new MBP right now and will be fixed with an OS update at some point. Or whether it's caused by the USB-C to DisplayPort adapters I am using.
  22. M3Jedi77 macrumors member

    Jun 30, 2007
    My 2016 MacBook Pro comes tomorrow. I'll be searching for ways to plug in my Dell 5k as well. Is there still no solid solution for this?

    Currently I have it connected to 2 TB2 ports out of my 2014 iMac, though I am replacing that with the MBP...
  23. rocker82 macrumors newbie

    Dec 15, 2016
    Well the two adapters I'm using are giving me a razer sharp image and for the most part working. But every once in a while I get a slight flicker in 1/4 of the screen and about 30% of the time coming out of a 10+ hr sleep, the screen comes back in a weird state (wrong resolution or only with the 5K showing a blown up view of half the screen) which is only correctable by pulling the power plug on the monitor, waiting a few seconds, and plugging it back in.

    Could very well be the adapters I'm using (Cable Matters) but sounds like people with other brands have had an even worse experience. At least in my case, it's working most of the time.

    Next on the list is trying without an adapter.. ie, buying two USB-C to DisplayPort cables.
  24. mulvone19 macrumors newbie

    Oct 12, 2015
    Cincinnati, Ohio
    I tried two USB C adapter and USB cables with DisplayPort but gave up because it was too inconsistent. Returning the display and getting the LG 5K instead. It'll have the forehead but I'll live with it.
  25. AppleSmack macrumors regular

    Jun 30, 2010
    Thanks so much for the updates, rocker82. This is such a shame. I've got the 5k on order, but really wish the Dell would work because of flexibility.

    Fingers crossed this is just a software update away, though it wouldn't surprise me if Apple Dell had somehow nobbled the 'standard'.

Share This Page

51 November 20, 2016