Connecting a Mac Studio to an HDMI 2.1 Display at 4k 120Hz

[JippaLippa]

Hello.

I purchased my M1 Ultra Mac Studio in march, but I was really disappointed in learning its HDMI port being 2.0 instead of 2.1 (the minimum for a machine of such price).

When connected to any sort of Apple Display this would not be a problem, as the thunderbolt ports have enough bandwidth to handle 4K 120HZ with HDR, but if you want to connect the mac to any other sort of 4K 120HZ display, you're left hanging as I cannot seem to find any reliable adapter from Thunderbolt 4 to HDMI 2.1 to purchase.

This was clearly a choice Apple made to steer its customets towards its displays, however I refuse to pay the obvious 3000$ (which will easily become 3500€) for the upcoming 27" mini-Led, when you can purchase gorgeous 42" oleds for half as much.

I know I could connect with the 2.0 port and be limited to 60hz, but I don't see why I should, especially on such an expensive machine.

Did you have any luck in using 4K 120hz on a mac studio? if so, what adapter did you use?

I'm aware there is a similar threads for regular M1s, but I wanted this one to be mac studio specific.

Thank you very much.

 

[Pressure]

No, it's a limitation of macOS currently.

DP to HDMI 2.1 adapters work in Windows but not in macOS for 4K120Hz.

 

[JippaLippa]

No, it's a limitation of macOS currently.

DP to HDMI 2.1 adapters work in Windows but not in macOS for 4K120Hz.

Doesn't make any sense to limit this, other than to push you to buy the upcoming apple 4k 120hz display.

Oh, then it makes very much sense (financially that is).

 

[tstafford]

When connected to any sort of Apple Display this would not be a problem, as the thunderbolt ports have enough bandwidth to handle 4K 120HZ with HDR, but if you want to connect the mac to any other sort of 4K 120HZ display, you're left hanging as I cannot seem to find any reliable adapter from Thunderbolt 4 to HDMI 2.1 to purchase.

Is this right? I don't know of any way to get more than 60hz from Apple desktops. I'm under the impression the only 120hz macs are the promotion laptops which also can't export above 60hz. This also makes me wonder about the upcoming mini-LED display - maybe Apple will use two thunderbolt ports to drive that monitor?

Am I wrong?

 

[joevt]

4K 120Hz (1188MHz) is less bandwidth than 6K 60Hz (1286MHz).

Apple doesn't make a 4K 120Hz display so they don't care if it doesn't work for M1/M2 Macs.

DisplayPort 1.4 (HBR3 25.92 Gbps) can do up to 2160MHz with DSC@12bpp. That would be enough for 8K 60Hz CVT-RB (2090MHz). I don't think anyone has achieved 8K from non-Intel Macs.

8K 60Hz is 2376MHz for HDMI which would require DSC@10bpp. DSC can go as low as 8bpp but no-one has tried less than the default 12bpp on macOS.

A Thunderbolt port has enough bandwidth for two HBR2 connections, 17.28 Gbps each. That's 1440MHz with DSC@12bpp. 6K 120Hz only requires 1361MHz for two tiles of 3008x3384. No-one has made a tiled display that uses DSC for each half.

Apple is able to get two HBR3 connections from Thunderbolt (each limited to 19.54 Gbps). Each could do 1628MHz using DSC@12bpp. All of Apple's DSC displays have been HBR2 - I don't know if Apple allows HBR3 with DSC. I don't know if Apple can make two HBR3 connections over Thunderbolt work on non-Intel Macs.

 

[JippaLippa]

Is this right? I don't know of any way to get more than 60hz from Apple desktops. I'm under the impression the only 120hz macs are the promotion laptops which also can't export above 60hz. This also makes me wonder about the upcoming mini-LED display - maybe Apple will use two thunderbolt ports to drive that monitor?

Am I wrong?

I'm sure apple will create a solution for promotion 5k HDR, the trouble is that it's going to be outrageously expensive.
An easy 3K$ which will magically become 3.5k€ in Europe; That's just too much for a 27" display.

 

[Zorast]

Fixed:

https://forums.macrumors.com/threads/usb-c-thunderbolt-3-4-to-hdmi-2-1-4k-120hz-rgb4-4-4-10b-hdr-with-apple-silicon-m1-m2-now-possible.2381664/