13" Macbook 2017 performance running an external 4k monitor?

Jimmy Mac

macrumors newbie
Original poster
Apr 25, 2010
16
4
Hi there,

I recently bought an external 4k monitor to use with my work macbook (details below). After buying new cables, I got it sync'd at 60hz, but even then the performance seemed to be pretty sluggish.

I was using Sketch mostly, and found that moving objects around or moving around the workspace was noticeably more sluggish than using the same MacBook on the 1920 x 1080 monitors at work. The problem did not seem to be limited to Sketch, though I admit I have not performed rigourous testing. The mouse trails on the desktop seemed laggy - like they were taking a while to catch up.

I ended up returning the monitor, as it was annoying me. I guess, what I would like to know:

  • Is it normal for this level of spec to perform poorly with external monitors at 4k?
  • What is my best bet for getting satisfactory performance on a larger screen? Are the 15" macbooks better at driving external displays and why? Are the 'in-between' screen resolution monitors a better bet (QHD)? Is an iMac just a better choice right now?
Screen: LG 27UD69P (27", 4k)
Laptop: Macbook Pro 13", i7, 16GB RAM, Intel IRIS graphics
 
Last edited:

MrGunnyPT

macrumors 65816
Mar 23, 2017
1,018
609
Hi there,

I recently bought an external 4k monitor to use with my work macbook (details below). After buying new cables, I got it sync'd at 60hz, but even then the performance seemed to be pretty sluggish.

I was using Sketch mostly, and found that moving objects around or moving around the workspace was noticeably more sluggish than using the same MacBook on the 1920 x 1080 monitors at work. The problem did not seem to be limited to Sketch, though I admit I have not performed rigourous testing. The mouse trails on the desktop seemed laggy - like they were taking a while to catch up.

I ended up returning the monitor, as it was annoying me. I guess, what I would like to know:

  • Is it normal for this level of spec to perform poorly with external monitors at 4k?
  • What is my best bet for getting satisfactory performance on a larger screen? Are the 15" macbooks better at driving external displays and why? Are the 'in-between' screen resolution monitors a better bet (QHD)? Is an iMac just a better choice right now?
Screen: LG 27UD69P (27", 4k)
Laptop: Macbook Pro 13", i7, 16GB RAM, Intel IRIS graphics
Hi mate I'm a system admin, but previously I had worked as a UX Designer for 5 years.. So I kinda understand your frustrations.

Is your model the nTB? The nTB model has poor downclock & thermal throttle on the GPU sadly.. This makes running 4k monitors a big ass pain (and one of the main reasons why I decided to wait for the last 2 years)

The reason the 15" drives things much better is because it has it's own dGPU instead of using the Intel iGPU for those kinds of heavy tasks.
 

Jimmy Mac

macrumors newbie
Original poster
Apr 25, 2010
16
4
Hi mate I'm a system admin, but previously I had worked as a UX Designer for 5 years.. So I kinda understand your frustrations.

Is your model the nTB? The nTB model has poor downclock & thermal throttle on the GPU sadly.. This makes running 4k monitors a big ass pain (and one of the main reasons why I decided to wait for the last 2 years)

The reason the 15" drives things much better is because it has it's own dGPU instead of using the Intel iGPU for those kinds of heavy tasks.
The laptop was the touch bar version, if that's what you mean? As per the note, it was an i7 with 16gb ram, so was surprised it wasn't snappy! The only weak link I could think of was the Intel GPU...

It wasn't totally unusuable, but definitely enough to make it a fiddly (trying to design on it felt like playing a laggy computer game!)
 

BiscottiGelato

macrumors 6502
Mar 11, 2011
286
72
This is a 2017 13"? I am using a 2013 13" with a 4k (Dell P2415Q) + 1440p HiDPI scaling at 51Hz. I was hoping going for the upcoming 2018 13" w/ TB would give drastic improvements + headroom. Sounds like not by much...
 

salivan

macrumors regular
Jun 10, 2015
131
40
I use 4k screen and have no problems.

mbpr2017 touch 16gb/i7 13inch

I also had 2014 13inch model and used it too on 4k screen on lower hz but without a problem.
 

CodeJoy

macrumors 6502
Apr 3, 2018
400
592
Hi there,

I recently bought an external 4k monitor to use with my work macbook (details below). After buying new cables, I got it sync'd at 60hz, but even then the performance seemed to be pretty sluggish.

I was using Sketch mostly, and found that moving objects around or moving around the workspace was noticeably more sluggish than using the same MacBook on the 1920 x 1080 monitors at work. The problem did not seem to be limited to Sketch, though I admit I have not performed rigourous testing. The mouse trails on the desktop seemed laggy - like they were taking a while to catch up.

I ended up returning the monitor, as it was annoying me. I guess, what I would like to know:

  • Is it normal for this level of spec to perform poorly with external monitors at 4k?
  • What is my best bet for getting satisfactory performance on a larger screen? Are the 15" macbooks better at driving external displays and why? Are the 'in-between' screen resolution monitors a better bet (QHD)? Is an iMac just a better choice right now?
Screen: LG 27UD69P (27", 4k)
Laptop: Macbook Pro 13", i7, 16GB RAM, Intel IRIS graphics
The symptoms you describe are consistent with what happens when the monitor ends up at a lower refresh rate. I have one of the early 4k displays that was JUST about starting to support 4k@60 Hz. However, it was an oddity that it will sometimes set itself to 30 Hz, and then I get exactly the symptoms you describe. In my case it ended up working well with mini display port, but not regular display port. Don't ask me why. I think the exact connectors and cables you use can end up influencing this quite a lot. Monitor settings could also be an issue. I seriously doubt that it's anything to do with the CPU or GPU itself. As long as we're just talking one monitor, any modern chip should drive it just fine. And you mention that you got it to sync at 60 Hz, so you may have had another problem.
 

Jimmy Mac

macrumors newbie
Original poster
Apr 25, 2010
16
4
The symptoms you describe are consistent with what happens when the monitor ends up at a lower refresh rate. I have one of the early 4k displays that was JUST about starting to support 4k@60 Hz. However, it was an oddity that it will sometimes set itself to 30 Hz, and then I get exactly the symptoms you describe. In my case it ended up working well with mini display port, but not regular display port. Don't ask me why. I think the exact connectors and cables you use can end up influencing this quite a lot. Monitor settings could also be an issue. I seriously doubt that it's anything to do with the CPU or GPU itself. As long as we're just talking one monitor, any modern chip should drive it just fine. And you mention that you got it to sync at 60 Hz, so you may have had another problem.
I wish I’d taken some time to record the symptoms. Like you say, they certainly were consistent with a lower refresh rate and were very pronounced while the monitor was connected at 30hz.

After trying a few cables, I was able to get it connected at 60hz (at least that’s what the System Report suggested) and all the scaling options were available. My observations...

  • Even at 60hz, mouse movements/dragging items around/tabbing was sluggish
  • Non-scaled was the snappiest, but everything looks really BIG
  • Having tried every monitor setting, I could not find anything that affected performance
I do wonder if I’m perhaps extra-sensitive to this, after playing competitive games on a 144hz monitor for years That said, I used this same mac for a year on 1920 x 1080 monitors at work and never once noticed an issue.

I might try and get into a a Mac store and see if they have MacBook hooked up to external monitors to try.

Can anyone recommend a decent high res external for the MBP?
 

Samuelsan2001

macrumors 604
Oct 24, 2013
7,694
2,123
I wish I’d taken some time to record the symptoms. Like you say, they certainly were consistent with a lower refresh rate and were very pronounced while the monitor was connected at 30hz.

After trying a few cables, I was able to get it connected at 60hz (at least that’s what the System Report suggested) and all the scaling options were available. My observations...

  • Even at 60hz, mouse movements/dragging items around/tabbing was sluggish
  • Non-scaled was the snappiest, but everything looks really BIG
  • Having tried every monitor setting, I could not find anything that affected performance
I do wonder if I’m perhaps extra-sensitive to this, after playing competitive games on a 144hz monitor for years That said, I used this same mac for a year on 1920 x 1080 monitors at work and never once noticed an issue.

I might try and get into a a Mac store and see if they have MacBook hooked up to external monitors to try.

Can anyone recommend a decent high res external for the MBP?
It’s a 13 inch thin light laptop with an iGPU the fact that it runs 4K at all is impressive. Go to a 1080p or a 1440p monitor is the only advice I can give you on this if you are sensitive to delay as you say.
 

CodeJoy

macrumors 6502
Apr 3, 2018
400
592
I do wonder if I’m perhaps extra-sensitive to this, after playing competitive games on a 144hz monitor for years That said, I used this same mac for a year on 1920 x 1080 monitors at work and never once noticed an issue.

I might try and get into a a Mac store and see if they have MacBook hooked up to external monitors to try.

Can anyone recommend a decent high res external for the MBP?
You may very well be extra sensitive, but I doubt that's what's causing the issue here. You're getting increased input lag for some reason, though it's unclear what that reason is. I've heard good things about the Acer H277HK, though I haven't tried it myself. Best would be to bring your laptop to a store and see if you can try a few screens. Second best would be to find a video with someone testing with the same laptop.
 
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