M1 macbook with external 4k HDMI display - scaling options.

[Ozbaab]

EDIT:
It was the dock that didn't work as intended. I bought a HDMI -> USB-C cable and now it works with correctly scaled options.



Hello,

New Mac owner here, I got the M1 Macbook Pro together with the LG OLED CX TV, which only has HDMI outputs.
When it comes to resolution the only thing I can choose is either normal 4k which is way too small, or HiDPI 1080p which is way too big.
I want atleast HiDPI 1440p or to be able to set my text size in 4k to be abit bigger. I'm not getting the "Larger Text ---- More Space" options as shown in the pictures below.

I've tried SwitchresX but it does not give me any new resolutions to choose from.

Is the M1 internal HDMI port worse when the older Intel Macbooks HDMI ports?

This is how it looks like when I'm trying to change resolution;
(Its in Swedish but you'll understand anyways)

And this is how another person sees his resolutions using the same monitor but another Macbook, not the M1:

So even though we are using the same monitor, using the same HDMI connection, we get different options regarding scaling and resolutions. The only different thing is I'm having the M1 macbook.

Thanks!

 

[Ozbaab]

I just discovered this thread which basically confirms it. The M1 can't do scaling like the Intel CPUs.

M1 MBP & LG 34 inch ultra wide 5K2K

I am using the M1 Mini with one of the LG 5K2K. It is connected via TB3 and functions as monitor and USB HUB (monitor sends 89 watts, why can't it do power also?) The monitor and USB hub works. Sometimes, but not always, the monitor doesn't wake up quickly from TB3. The computer is on and...

forums.macrumors.com

 

[Christopher Kim]

I just discovered this thread which basically confirms it. The M1 can't do scaling like the Intel CPUs.

M1 MBP & LG 34 inch ultra wide 5K2K

I am using the M1 Mini with one of the LG 5K2K. It is connected via TB3 and functions as monitor and USB HUB (monitor sends 89 watts, why can't it do power also?) The monitor and USB hub works. Sometimes, but not always, the monitor doesn't wake up quickly from TB3. The computer is on and...

forums.macrumors.com

Thanks for linking the thread - I just read through it and it was really interesting.

To summarize for others, there seems to still be an M1-limitation where you cannot get HiDPI-scaled resolutions that are greater than 3008x1692 (specifically anything wider than 6K pixels horizontal when pixel-doubled).

You can do so in native mode (ie. not pixel-doubled), but not in HiDPI scaled mode.

However, @Ozbaab, if I'm understanding your situation, this should not limit what your'e trying to do. All you're trying to do is get 1440p HiDPI (ie. 5120 x 2880, which is then scaled down to "Looks like 2560 x 1440"). Given this is lower than the apparent M1-limitation of showing any "Looks like" resolution greater than 3008x, you should still be able to do so with your M1. Given that, I wonder if it's something else with your setup. What kind of cable / adapter setup are you using to connect your TB3 port -> HDMI monitor?

 

[Ozbaab]

Thanks for linking the thread - I just read through it and it was really interesting.

To summarize for others, there seems to still be an M1-limitation where you cannot get HiDPI-scaled resolutions that are greater than 3008x1692 (specifically anything wider than 6K pixels horizontal when pixel-doubled).

You can do so in native mode (ie. not pixel-doubled), but not in HiDPI scaled mode.

However, @Ozbaab, if I'm understanding your situation, this should not limit what your'e trying to do. All you're trying to do is get 1440p HiDPI (ie. 5120 x 2880, which is then scaled down to "Looks like 2560 x 1440"). Given this is lower than the apparent M1-limitation of showing any "Looks like" resolution greater than 3008x, you should still be able to do so with your M1. Given that, I wonder if it's something else with your setup. What kind of cable / adapter setup are you using to connect your TB3 port -> HDMI monitor?

Hey, thanks for your reply!

I have it connected to a dock, Amazon link (in Swedish tho), it's supposed to support 2x 4k60hz screens or 1x 5k screen. Have tried with a HDMI 2.1 cable.

I could try and get a USB-C -> HDMI connector to see if it's the dock preventing me from setting the resolution, haven't tried that yet. (Or a thunderbolt -> HDMI connector, but that's the same thing no?)

What I have tried is a HDMI -> DisplayPort cable, so from TV with HDMI --> into the dock with DisplayPort --> then from the dock with USB-C into the Macbook.
The dock has both HDMI and DisplayPort so I wanted to see if using the DP port in the dock instead of the HDMI would make a difference, it didn't.


EDIT:
Alright so I ran to the store and got me a HDMI -> USB-C cable and now it works! So it was the dock all along.
Thank's alot @Christoffer Kim, without you I would've just accepted that it would not have worked!

 

[Christopher Kim]

EDIT:
Alright so I ran to the store and got me a HDMI -> USB-C cable and now it works! So it was the dock all along.
Thank's alot @Christoffer Kim, without you I would've just accepted that it would not have worked!

Great to hear! Yea, looking through the Amazon link for the dock, it does appear it was made for Windows PCs, not Macs. Even though it technically works with Macs, not surprised that there were issues with HiDPI as that's a Mac-specific feature.