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How many 4k 120hz displays on an M2 Max MacBook Pro?
- Thread starter SafariX
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You need a USB-C to HDMI adapter. More info here: https://forums.macrumors.com/thread...ith-apple-silicon-m1-m2-now-possible.2381664/
Sorry about this but wanted to quickly ask you a question... I am searching for a new external display to pair with my M1 macbook pro (locked at 60 hz refresh rate unfortunately).
I am strongly considering the c2 OLED 42". How is it with productivity and general use? I don't really game on my mac either. Also, hows the text look?
Thanks
That's based more on which adapter you purchase. Some only support 4K/60, so you want to make sure the one you buy supports 4K/120.
Any updates on this? I'm wondering if the M2 Max Macbook Pro can drive three 4k displays at 120hz.
From Apple's website:
They're listing possible configurations as follows:
(TB4) (HDMI)
3 6k60 + 1 4k144
2 6k60 + 1 8k60 OR 1 4k240
I think the issue with pushing 3 4k120 displays is simply the TB and HDMI specs themselves.
They're listing possible configurations as follows:
(TB4) (HDMI)
3 6k60 + 1 4k144
2 6k60 + 1 8k60 OR 1 4k240
I think the issue with pushing 3 4k120 displays is simply the TB and HDMI specs themselves.
6K 60 Hz has a bit higher bandwidth requirements than 4K 120 Hz.
The 6K 60 Hz models require Display Stream Compression for 10-bit color and so do the 4K 120 Hz displays when used over DP Alt Mode. So it becomes a question of DSC working with multiple 4K 120 Hz monitors really.
Note that additional limitations can come into play because of Apple's ****in' stupid scaling implementation. It seems that instead of upscale 2x -> downscale to native -> send to display, MacOS just sends the scaled resolution to the display and lets it handle the scaling. This has curious effects like HDR not working at 4K 120+ Hz if you also set scaling to a fractional scaling setting instead of native res or 1:1 (1080p) scaling.
I'm currently running M2 Max with 5 displays (including the in-built display) at the same time:
3840x2160@144fps
3840x2160@120fps
3456x2234@120fps (in-built display)
3840x2160@60fps
3840x2160@60fps
Everything runs smoothly. One small thing - if the computer is restarted with all monitors plugged in, one of the monitors starts having significant latency. Reconnecting that monitor fixes it until the next restart with all the monitors is plugged in.
I can also confirm that it's possible to connect an iPad 12.9" as a native 6th display (I wanted to use a cable, and since there's no 5th USB-C port so I had to use Caldigit TS4 dock).
This means that the "4 external monitor" limitation does not apply to iPads (Sidecar), weirdly.
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Any cable that has sufficient data throughput specification will work perfectly.
I suggest avoiding extremely cheap cables sent directly from China since they might lie about the specifications.
For 4K 60Hz monitors
- Product specification includes "20Gbps" or "4K @ 60Hz"
- USB-C to USB-C cables if your monitor has a USB-C port. Otherwise, pretty much any USB-C to DisplayPort cable should work perfectly fine.
- length 3.3ft or 6.6ft (i.e. 1 or 2 meters)
- Usually costs around 15$ for a 6.6ft cable (Specifically, I bought "IVANKY USB C to USB C Cable" from Amazon)
For 4K 144Hz monitor #1
- HDMI to HDMI cable (if your monitor has HDMI 2.1 port)
- Product specification includes "48Gbps" or "8K @ 60Hz" or "HDMI 2.1" or "HDMI Ultra High Speed"
- Normally, you should be able to use the HDMI cable that came with the monitor
- If your monitor has multiple HDMI ports, they may have different speeds. If you correct the slower HDMI port, it will be limited to 60 Hz instead of 120 Hz (or 144 Hz).
For 4K 144Hz monitor #2
- I use a "Cable Matters" USB-C to DisplayPort cable
For connecting the iPad as a 6th screen, I use "CalDigit TS4 Thunderbolt 4 Dock". This dock comes with a cable that connects to the Mac. Then I connected a monitor to it through a DisplayPort-to-DisplayPort cable, and the iPad through a USB-C to USB-C cable (I used a 20Gbps cable, which worked perfectly).
I forgot to mention that I have the 38 Core GPU version (as opposed to 30 Core) of the M2 Max which may or may not be the reason everything runs smoothly.
Hey sromurs, can your set up run 120hz+ on 3 external 4k displays? Perhaps closing the lid of the macbook would let one of the other 3840x2160 screens ramp up fps?
My goal is to have 3 external 50" 4k monitors all running at 120hz. In this scenario the macbook would be closed and hiding somewhere on the back of my desk.
My goal is to have 3 external 50" 4k monitors all running at 120hz. In this scenario the macbook would be closed and hiding somewhere on the back of my desk.
m2 max officially supports 3 external displays of 6K resolution at 60Hz.
Apple Pro Display XDR is 6K resolution with 6016×3384. Considering three 8bit colors, the bandwidth is
6016*3384*60=1.221 billion pixels per second.
For 120hz 4k the needed bandwidth is 3840*2160*120=0.996 billion pixels per second.
For 144hz 4k the needed bandwidth is 3840*2160*144=1.194 billion pixels per second.
So 6K 60 Hz is technically more demanding than 144Hz 4K.
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I don't have a third 144Hz or 120Hz monitor to test this, but my I would guess that three 4K 144Hz/120Hz should work, especially if would connect one of the monitors through the HDMI 2.1 port (because if I'm not mistaken, HDMI gets a separate video throughput lane from the system, or something effectively like it)
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"closing the lid of the MacBook"
So far my impression is that Apple deliberately avoids different capabilities based on whether the lid is open or not. While some windows laptops I had, actually allows for this (i.e. if you close the lid, you can connect and extra external screen for example). Apple approach makes the system more predictable, and harder to mess up for less tech savvy users, at the expense of customizability.
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Following up on this. I tested out my M2 Max Macbook Pro and M3 Max Macbook Pro with three 4k 144hz (28” Odyssey G70B) monitors. Two are plugged in via DisplayPort 1.4 and the third via HDMI 2.1. If I drop the refresh rate to 120hz I can enable HDR on all three. I'm also seeing that using scaled resolutions works at 144hz just fine even though internally macOS is doubling the resolution (6720x3780).
Everything works just the same on both M2 and M3. I did have some issues with the monitor plugged in via HDMI, though. If I didn't have it properly set to PC mode in the monitor's onboard settings it would cap out at 120hz instead of 144hz.
System report screenshots:
