1

I have a Late 2013 MacBook Pro with NVIDIA GeForce GT 750M 2GB graphics card running macOS High Sierra 10.13.1, and when I attempt to connect 3 4k screens (2 Mini DisplayPort, 1 HDMI) while running the internal screen, all screens go blank, and the system freezes until I hold in the power button to force power off.

Things I've tried:

  • Using just the 3 4k screens without the internal (this works, but doesn't allow me to use the internal)
  • Using 3 non-4k screens (1080p + 2k + 2k) and (1080p + 4k + 2k) with the internal (this works)
  • Using 1080p + 4k + 4k + internal (this crashes the system)
  • Unplugging one screen after it freezes (system is still frozen)
  • Checking the logs (couldn't find anything (maybe I'm looking in the wrong place), and there's no kernel panic log)
  • Plugging in the 3 screens and then opening the laptop to turn on the internal screen (Freezes like before)
  • Booting with everything plugged in (It just doesn't finish booting)
  • Booting to recovery with everything plugged in (gets stuck on the apple with progress bar)

My computer has no trouble with the 3 screens without the internal (low CPU, not running slow), so it doesn't seem like it's just getting overloaded.

I know this computer can drive 4k screens and can also drive 3 externals plus the internal, but maybe I'm hitting some undocumented limit here by trying to combine them. Is there anything else I can try or somewhere I can look to see what the error is?

I'm considering getting a 4k compatible USB -> HDMI video adapter to drive the screen I won't use as much, but I'm not sure if that will trigger the same issue, and I'd like to see if there are any other ideas.

Hardware stats:
  Model Name:   MacBook Pro
  Model Identifier: MacBookPro11,3
  Processor Name: Intel Core i7
  Processor Speed: 2.3 GHz
  Number of Processors: 1
  Total Number of Cores: 4
  L2 Cache (per Core): 256 KB
  L3 Cache: 6 MB
  Memory: 16 GB
2

When you say you know your MBP can drive 4k screens and can also drive 3 externals plus the internal, on what basis do you say this? In fact, this is well beyond what this model is officially capable of doing.

Your MBP officially supports an HDMI-compatible device, including 4K, while using one Thunderbolt Display. Or, it can support up to two Thunderbolt displays.

In terms of actual resolution outputted to an external display, it supports up to 3840x2160 pixels at 30Hz or 4096x2160 pixels at 24Hz (HDMI), or up to 3840x2160 pixels at 30Hz on two external displays via Thunderbolt.

Of course the above is the official position. Your testing has shown you that you can exceed this, but what you’re wanting to do is beyond what I’d recommend.

You may find my answer on another question of interest, especially in terms of real life scenarios. The MBP in that question is not the same model as yours, but the overall findings still apply.

  • I thought I had read at one point in official docs that my computer could run 2 Thunderbolt + 1 HDMI + internal and that the 13 inch model was the one that couldn't run internal with that combination, but maybe the docs changed or I don't remember correctly. Oddly, I'm also getting 60 Hz on the two thunderbolt screens, so maybe they're MST and I didn't realize it. – Joshua Dwire Dec 2 '17 at 21:43
  • Other than slowing things down, what would be potential consequences of overdoing it? I'm at 10% CPU usage and a temperature of 56 C at the CPU with the three external 4K. I'm doing software development, and not any graphics intensive work. – Joshua Dwire Dec 2 '17 at 21:45
  • In your case you probably wouldn’t really tax the CPU too much because your model MBP has a dedicated GPU, and connecting all those screens should switch it over to that GPU instead of the Intel Iris Pro that’s part of the CPU. However, what it will mean is that the GPU will generate more heat than it would normally. Depending on what you’re doing at the time, if it generates enough heat then it may trigger the System Management Controller’s protective measures to protect the MBP from harm. – Monomeeth Dec 2 '17 at 23:23
  • However, if you’re connected to three displays in clamshell mode (or two displays normally) you should be fine. Just be aware though that within the tight confines of a MBP heat will travel and be picked up by multiple sensors, and that’s when you may experience the SMC doing its thing (e.g. fans spinning faster, etc). So, my recommendation is that if you ever need to do anything that is graphics intensive (playing games, video editing, etc) you’d be better to disconnect one of the displays first. – Monomeeth Dec 2 '17 at 23:30
  • Thanks! I'm sticking with the 3 external 4k for now without trying to figure out how to get the internal working. (My desk doesn't have room with my current setup.) I have a cooling pad, which may be helping a little bit. – Joshua Dwire Dec 4 '17 at 16:24

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .