2

I will be using the MacBook Pro (16-inch, 2021) with the Apple M1 Pro 10 core CPU, 16 core GPU mostly for programming(python, machine learning, deep learning and docker) and davinci resolve(only for video editing). I have read a lot of articles online. some said that only 1440p or 5k must be used for a 27” monitor, while some said that 4K can be used, but only after sacrificing a significant amount of CPU/GPU power for scaling for the unsupported PPI, while some other articles mentions that third party tools can be used for proper scaling.

So, I would like to know, from the community, how to go about this?

I need a 4K monitor(not other resolution), but can’t afford LG Ultrafine 5K(couldn’t find other 5K monitors) at this moment!. and anything above 27inch would be too big.

bmike
  • 235,889
Naveen Reddy Marthala
  • 145
  • 1
    Which processor did you choose in your MacBook Pro? Knowing the cores may help us help with experience. For programming I haven’t seen a single issue with one large 6k display on even the lowest spec M1 – bmike Sep 19 '22 at 17:05
  • 1
    The only bad choice you could make with one display is a bad adapter / too cheap a display. Thunderbolt displays are going to be premium in terms of speed, then display port, finally HDMI most finicky and opening you to cheap adapter issues. The Mac won’t be the problem here IMO. I’ll try to get a proper “don’t do this dual display” answer up later but you want one ultra wide display not two 27 for this Mac. Two extra displays don’t chain and aren’t officially supported. – bmike Sep 20 '22 at 07:09
  • 1
    I’ll turn my comment into an answer a bit later. You’ve got great options with that GPU now - change my “one” to “two” from the comment basically. – bmike Sep 20 '22 at 08:02
  • i read the answer you linked. from your testing, can you confirm me a couple things please. I would like to use two 27inch BenQ 4k monitors(PD2700U) with a display port, not considering wide angle at this point. and would like to use them at 60Hz refresh rate, even though monitors max is 160Hz. each monitor from a type-c port on each side with type-c to display port v1.4 of monitor directly. will this use additional CPU(or GPU resources)? how worse can this setup go for my use cases(coding and editing on davinci resolve)? – Naveen Reddy Marthala Sep 20 '22 at 08:03
  • 1
    @bmike, in your answer, please also talk about using the monitors at 10-bit color at 60Hz with type-c to DP v1.4 connected via ports at either side of the MBP. i might even switch to 28inch monitors if that can make things better. – Naveen Reddy Marthala Sep 20 '22 at 08:24
  • 1
    Why not use LG UltraFine 4K Display? Avoids all the issues you mention

    https://store.apple.com/xc/product/HMUA2VC/A

     – bmike Sep 21 '22 at 11:14
  • thanks @bmike, so, when I connect 16'' MBP to two 27 inch LG Ultrafine 4K displays via type-c at either side of laptop to type-c port of monitor, I will have proper scaling(text and windows) and not have any increased CPU or GPU usage, and should able able to run both displays at 60Hz at 10-bit color, correct? two questions, 1. can I connect each of the display to a USB-C dock that is connected to MBP and still have all the aforementioned benefits? – Naveen Reddy Marthala Sep 21 '22 at 14:21
  • 1
    Do not choose a cheap dock. Test first with direct connections. – bmike Sep 21 '22 at 15:41
  • this is the dock i plan to buy (Anker PowerExpand 5-in-1 Thunderbolt 4 Mini Dock at https://www.anker.com/products/a8398?variant=41093989892246 )[may be more than one]. i need the additional ports to use external keyboard, mouse, an external usb audio interface(to which i would connect my microphone), a drawing board, usb webcam, wired headset, ethernet cable and external hard drive (seagate one touch hub). – Naveen Reddy Marthala Sep 21 '22 at 17:19

3 Answers3

1

This has been a misunderstanding from the beginning. You first mentioned a M1 MacBookPro which has been sold by Apple over the last two years. I have written my answer in belief that you are using that model, however, now you updated the question and you are using a M1 Pro MacBook Pro 14", which is a different chip and therefore supports more displays!

M1 Pro MacBook Pro

The M1 Pro chip supports two external screens, each at a resolution of up to 6K@60Hz. For full details view the Apple spec sheet.

M1 (without Pro or Max) MacBook Air/Pro

The M1 chip only supports one single external display with a resolution of 6K@60Hz. For example, see the details for the (old) M1 MBP 13".

Generally any connected screen will take some hit on the performance, but it is such a minor performance drawback that IMO it is always better to have more screen real estate. However, when you need more external displays than whats supported out of the box you can use DisplayLink. You will end up with a higher CPU/GPU load though, which can also vary a lot depending on what you are doing.

I can't give much advice on scaling - I have not tried around too much, but for me the usage (when I had been using DisplayLink) was ok, usually below 10%. However, this also depends on what you are doing (dragging windows around is harder than just writing some text in Word/VSCode). IMO I would just try it out, since this depends on so many devices in your setup it is hard to give exact numbers. Similar things have been reported in the DisplayLink forum.

X_841
  • 3,386
  • I had mentioned macbook pro, not the air. and it does support more than 1 external monitor. – Naveen Reddy Marthala Sep 19 '22 at 16:38
  • i am very well aware that MBP can handle 2 external 4k monitors. and my question was to learn what to do to avoid sacrificing CPU performance when using the monitors that usually do not align with what mac OS expects. – Naveen Reddy Marthala Sep 19 '22 at 16:40
  • Sry I sort of "defaulted" to MBA when reading M1 processor. See my updated answer although it might not be much of help. IMO I would just try it out! – X_841 Sep 19 '22 at 17:08
  • from the 3 thunderbolt ports, if i connect each monitor to one usb port, directly or using an usb hub, i wouldn't have to use direct link at all, correct? and hence no such drastic performance decrease? – Naveen Reddy Marthala Sep 20 '22 at 05:32
  • You have now changed your Mac model, I therefore had to update my qestion again. However, the M1 Pro MacBook still does only support two external screens without additional hardware, so no, using all three Thunderbolt/USB ports for three displays will not be possible, unless one of them is connected through a DisplayLink hub. – X_841 Sep 20 '22 at 07:51
1

CPU and GPU always go up when you push pixels. The question is balance and expectations. I’ve not had any bad interactions with the LG 5K and 4K displays sold through Apple.

Other than appropriate and manageable ghosting on the panels (burn in that’s normal and expected on mid to high quality LCD) there have been no issues with several of Mac hardware up to and including M2 lineup.

If you are making money with your time or computer, avoid DisplayLink entirely.

They aren’t as high quality or feature full as Apple displays, but they are very good for pro use IMHO.

bmike
  • 235,889
1

Since you plan to use the setup for writing a lot a code I highly recommend you to stick with 1440p display since macOS scaling does not work correctly with 4K and you will never get a pixel-perfect scaled display output on 4K display (and native 4K will be too small for code). For in-depth explanation regarding this issue and please refer to this article (contains list of HiDPI displays that may be used with macOS scaling, i.e. Dell UP2715K) and this video (for a perfect example).

P.S. Believe me your eyes will hurt on 4K because image will be slightly blurry when macOS scaling is on. Don't waste your time and money with 4K.

bananakid
  • 83