MP All Models SOLVED: 8k Displays Running on Mac Pro? Any? What Video cards would work that support 8k HDMI 2.1/Displayport 1.4/2.0 displays on Mac Pro? YES you can

[ZombiePhysicist]

BTW for those that want to see the setup a little bit more, wrote up little about it here:

https://forums.macrumors.com/threads/what-does-your-home-office-look-like-mac-pro-7-1-but-everyone-welcome-to-share.2372233/post-31774931

 

[ZombiePhysicist]

Well the m2 pro/max laptops came out supporting 8k HDMI video today, so maybe this kind of craziness won’t be needed with whatever updated is/drivers they release for the new machines!

 

[csdesigns]

This is what I was hoping as well, but if you look at the specs, this is probably not the solution we were all hoping for:

One external display supported at 8K resolution at 60Hz or one external display at 4K resolution at 240Hz over HDMI

So that limits 8K output solely to HDMI 2.1 connections on the new MBPs. Doesn't look like Thunderbolt displays will be receiving the same support, as the specs specifically state:

up to 6K resolution at 60Hz over Thunderbolt

Doesn't look like drivers have yet added support for 8K over Thunderbolt, even on the new MBPs

 

[ZombiePhysicist]

This is what I was hoping as well, but if you look at the specs, this is probably not the solution we were all hoping for:

So that limits 8K output solely to HDMI 2.1 connections on the new MBPs. Doesn't look like Thunderbolt displays will be receiving the same support, as the specs specifically state:

Doesn't look like drivers have yet added support for 8K over Thunderbolt, even on the new MBPs

I don’t think we will get 8k on thunderbolt until thunderbolt 5. :/

 

[csdesigns]

I don’t think we will get 8k on thunderbolt until thunderbolt 5. :/

Unfortunately, you're most likely along the right train of thought. My initial hope upon the headlining announcement was that the drivers could at least be back-ported to other TB4-capable machines, but that still appears to be just a dream...

 

[ZombiePhysicist]

Unfortunately, you're most likely along the right train of thought. My initial hope upon the headlining announcement was that the drivers could at least be back-ported to other TB4-capable machines, but that still appears to be just a dream...

I wonder if it will at least make cards with HDMI 2.1 ports like the 6900xt I have, work without jumping through flaming hoops. Just use a straight HDMI 2.1 cable and get full color fidelity etc at 60hz without the weird rubegoldberg setup I got going to make mine work.

 

[startergo]

I don’t think we will get 8k on thunderbolt until thunderbolt 5. :/

 

[penfold1251]

Also just saw the news about the new M2 Pro supporting 8K60 over HDMI. May need to wait for the Mac Studio equivalent to get >32GB RAM though!

I have reproduced 8K on macOS with a similar setup to @ZombiePhysicist:

• Mac Mini 2018 (64GB/2TB/10G running Monterey)
• AMD RX 6600 XT (ASRock Challenger ITX as eGPU via Akitio Node Pro -- cheapest model I could find supported by macOS Monterey+)
• Samsung QN900A (65" Australian model; unfortunately I'm waiting on a replacement because one corner of the display has intermittent faulty backlights... almost perfect when it works though, just one dead pixel in the top left near the menu bar which is hard to even find... kinda crappy uniformity for all-white screens, as noted in the Rtings review, but fine for my purposes)
• CableDeconn DisplayPort 1.4 to HDMI 2.1 Ultra HD 8K Male to Female Cable (https://www.amazon.com.au/dp/B0B1C2FDLN)

Windows 10

• 7680x4320 @ 60Hz 4:4:4 via HDMI 2.1 port
• All the adapters work too but only at 60Hz 4:2:0 or 30Hz 4:4:4.

macOS Monterey

• 7680x4320 @ 60Hz 4:2:0 via DisplayPort using CableDeconn male to female adapter (reasonably stable but occasionally the signal drops out; have had many hours without issue though)
• 7680x4320 @ 30Hz 4:4:4 also works but is unstable (screen starts tearing after a while)

I found that scaling to 5K using Better Display is quite usable at around 70-100cm. Other higher scaled resolutions wouldn't stay put (would revert back to 4K regularly). This setup can't seem to play 8K YouTube videos smoothly (and grinds to a halt)... haven't tried using Windows though.

Could not get the adapter @ZombiePhysicist used to work properly under macOS:
CableDeconn DisplayPort 1.4 to HDMI 2.1 (https://www.amazon.com.au/dp/B0994FPCMD)
The TV showed a signal for 7680x4320 @ 60Hz or 30Hz but the screen was always black. Eventually the 30Hz mode would show a corrupted desktop but not refreshing anywhere near 30Hz.

Was hopeful that the Club 3D CAC-1085 (https://www.club-3d.com/en/reviews/11/cac_1085_the_ultimate_connection_for_dp_to_hdmi_4k120h/) would work but no luck on macOS. Only got 60Hz 4:2:0 under Windows. Updated the firmware to 1.09 (via Club 3D support email who noted that macOS 8K is not supported). Disappointing as it was by far the most expensive option.

Many thanks to everyone who shared info in this thread! Especially @ZombiePhysicist for the reminder on the bizarre UX of SwitchResX and @joevt for detailed instructions on how to use AGDCDiagnose + AllRez to see what mode is actually being used.

 

[ZombiePhysicist]

That’s great that you got it to work! Congrats! Hopefully the update that comes out in a couple of weeks will let us just use a full 2.1 cable and things will work super solid. Fingers crossed.

 

[ZombiePhysicist]

So I just updated to Ventura 13.2 and decided to unplug my 'magic 8k cable' and try a regular HDMI 2.1 cable. Weird results. TLDR it didnt work and probably requires more fiddling than I have time for right now.

But SwitchRexX doesnt show the 8k resolutions and when I try custom resolutions at 8k, it just doesnt work. With the magic cable, the 8k resolution are displayed as options.

But 13.2 did do something. It's hard to explain, but when flipping from and back to 8k resolution, before the 13.2 update, the way the screen came on was with this hard flicker. But now it just appears softly at the right resolution. So 13.2 is doing something different.

The hope was since apple is releasing 13.2 for new laptops HDMI2.1 ports on the Mac book pros that supports 8k, that the 6900XT (which has an HDMI 2.1 port) would auto-magically just work.

Well so far that's not happened. I'll try and play with this more throughout the week though. Maybe others will have better luck.

 

[hardwickj]

Worth mentioning to you guys that MacRumors tested the new M2 MacBook Pro's HDMI port w/ a Samsung 8k TV, and it appeared to work without a hitch:

 

[ZombiePhysicist]

Ok so I tried again with a straight HDMI 2.1 cable and no go. First, the Display panel in system settings does not show resolution options but just 'show more/less' options and keeps the resolution stuck at 4k

.
Second, the list of current resolutions in SwitchRezX does not show any 8k resolution options as follows, it shows some weird 6k option as a max:

The custom 8k resolutions in the custom tab are something I cannot activate no matter how I try to push the 'activate' button, it just stays on one of the settings in the current resolution tab as such:

For a contrast, when I use my 'magic DisplayPort to HDMI 8k cable" the current resolutions show 8k at 30hz and 60hz (although only the 60hz setting works), as such:

What is also interesting is that the 8k resolutions are shown as "best resolutions" with the magic cable. Something changed because at least before 13.2 when I used the regular HDMI 2.1 cable, I could get the scaled 8k option but now nothing I put into the custom resolution panel changes what is available in then current resolution panel.

But weirdly, now the magic DisplayPort to HDMI 8k cable seems to lock and work better than before at hitting and staying in the 8k resolution.

So something changed, but it's not clear what. But for now, I cannot get the 6900xt to pump out 8k video via HDMI 2.1. :/

 

[penfold1251]

The custom 8k resolutions in the custom tab are something I cannot activate no matter how I try to push the 'activate' button, it just stays on one of the settings in the current resolution tab as such:

Earlier in this thread @joevt mentioned that instead of using "Activate Immediately" you can disconnect/reconnect the cable. You may already know about this but I found that a convenient way to do this without fiddling with cables is to hold down the power button on the remote until the One Connect box audibly clicks (like a relay opening/closing I guess?). This causes the QN900A to turn off completely instead of soft powering off (~sleeping). In my testing this sometimes worked better for getting the valid 8K resolutions to show up. Still requires multiple attempts sometimes, though, as you originally described.
EDIT: To note that it is still necessary to use Cmd+S to save the changes before doing this. SwitchResX UX is weird.

(The "best" part is that I found out about this trick some time ago due to our actual Samsung television having weird flickering issues that can be avoided by turning off the "fast wake" setting, or doing this remote-based trick... ahhh, technology... )

 

[Arvine]

Second, the list of current resolutions in SwitchRezX does not show any 8k resolution options as follows, it shows some weird 6k option as a max:

This happened to me also some weeks ago when I upgraded to Ventura 13.0.1. (Note sure if it could be due to a newer version of SwitchResX or new firmware to my Samsung Q800A.)

Something changed because at least before 13.2 when I used the regular HDMI 2.1 cable, I could get the scaled 8k option but now nothing

Scaled 8K went away for me also.

But weirdly, now the magic DisplayPort to HDMI 8k cable seems to lock and work better than before at hitting and staying in the 8k resolution.

I never got my “magic cable” to work with 8K native. I.e. the Cablematters active Dp1.4 to HDMI 2.1.

 

[Rams1976]

4k 120 with sound! I plugged in a an active Club3D display port to HDMI adapter and then removed my 8k HDMI cable and plugged it into the HDMI 2.1 port on my GPU leaving the Club 3D still plugged in and VOILA! Sound through the TV via HDMI and 4k@120hz on a 2010 MacPro and RX6600XT!!!! FINALLY Tru Motion Scrolling on my 48inch OLED and Mac OS!!!!

 

[ZombiePhysicist]

Btw audio has been working from my TV all along. I never thought to mention it but for those who want to use it, it works for me too.

 

[Pressure]

4k 120 with sound! I plugged in a an active Club3D display port to HDMI adapter and then removed my 8k HDMI cable and plugged it into the HDMI 2.1 port on my GPU leaving the Club 3D still plugged in and VOILA! Sound through the TV via HDMI and 4k@120hz on a 2010 MacPro and RX6600XT!!!! FINALLY Tru Motion Scrolling on my 48inch OLED and Mac OS!!!!

4K 120Hz YCBCR420 works fine on HDMI 2.0 though. With HDMI 2.1 you should be getting YCBCR444.

 

[hardwickj]

Apparently someone got the UP3218K working at 8K60 on an M2 Max MacBook Pro running 13.2, simply using two USB-C to DisplayPort 1.4 cables!

EDIT: Waiting to hear back from him if MacOS correctly detects it as a single screen of it treats it as two separate displays...

Would this allow the Dell UP3218K monitor to work at 8k@60hz? · waydabber BetterDisplay · Discussion #199

The Dell UP3218K is the only 8k computer monitor on the market at the moment. Unfortunately, the only connectivity it offers is 2xDisplayPort 1.4 without DSC, with each cable comprising half of the...

github.com

 

[Pressure]

Apparently someone got the UP3218K working at 8K60 on an M2 Max MacBook Pro running 13.2, simply using two USB-C to DisplayPort 1.4 cables!

EDIT: Waiting to hear back from him if MacOS correctly detects it as a single screen of it treats it as two separate displays...

Would this allow the Dell UP3218K monitor to work at 8k@60hz? · waydabber BetterDisplay · Discussion #199

The Dell UP3218K is the only 8k computer monitor on the market at the moment. Unfortunately, the only connectivity it offers is 2xDisplayPort 1.4 without DSC, with each cable comprising half of the...

github.com

The dock appears to be in the middle as expected for a single 7680x4320 display instead of the two 3840x4320 I currently get.

If that's the case Apple better hurry up and upgrade the Mac Studio to M2 Max ...

 

[Pressure]

Well it appears to just work and be detected as a normal monitor.

Dell UP3218K working on M2 Max. Update: Now also confirmed to work with the M2 Pro.

 

[hardwickj]

Another user confirmed it works on an M2 Pro Mac Mini

 

[Pressure]

Another user confirmed it works on an M2 Pro Mac Mini

If only Apple would hurry up and upgrade the Mac Studio to the M2 Max ... 😅

 

[penfold1251]

After reading some rumours that the Mac Studio wasn't getting an M2 refresh, I decided to go with a Mac Mini M2 Pro for now. 8K60 over HDMI 2.1 works out of the box with the QN900A. Also supports VRR ~48-60Hz and the HDR option is available...

However, it looks like it might not be 4:4:4 (bad text clarity in parts using the rtings test pattern). I also get weird artifacts when enabling HDR. Not sure if there's any way to verify the pixel encoding on Apple Silicon? AGDCDiagnose doesn't work and AllRez gives some info but segfaults.

Annoying but good enough for my purposes, as I was previously using 4:2:0 anyway. Strangely it looks worse now but only noticeable on the test pattern. Maybe an OS update will improve things but not sure I can really do anything in the meantime as SwitchResX doesn't seem to be able to do custom resolutions/timings.

Now that I've upgraded Apple is free to release the Mac Studio M2 series next week...

 

[Pressure]

Now that I've upgraded Apple is free to release the Mac Studio M2 series next week...

Thanks for your sacrifice 😂

 

[ZombiePhysicist]

After reading some rumours that the Mac Studio wasn't getting an M2 refresh, I decided to go with a Mac Mini M2 Pro for now. 8K60 over HDMI 2.1 works out of the box with the QN900A. Also supports VRR ~48-60Hz and the HDR option is available...

However, it looks like it might not be 4:4:4 (bad text clarity in parts using the rtings test pattern). I also get weird artifacts when enabling HDR. Not sure if there's any way to verify the pixel encoding on Apple Silicon? AGDCDiagnose doesn't work and AllRez gives some info but segfaults.

Annoying but good enough for my purposes, as I was previously using 4:2:0 anyway. Strangely it looks worse now but only noticeable on the test pattern. Maybe an OS update will improve things but not sure I can really do anything in the meantime as SwitchResX doesn't seem to be able to do custom resolutions/timings.

Now that I've upgraded Apple is free to release the Mac Studio M2 series next week...

Wow that’s interesting and a touch disappointing.