4k@144Hz no longer available after upgrade to Big Sur
MacRumors has a megathread about this issue
Not seeing any actual reports of it being fixed just someone saying "I think it's fixed on 11.3 version" but their issue is slightly different.
If anything, I think it's a lot of people being confused by this post:
Just tried on MACBOOK Pro 16'' 5500M 11.3 beta2 ，The problem has been finally fixed. dp 1.4 4K 144HZ HDR.
But this is incorrect. The user above uses a 2K monitor, not 4K, so the only issue that was fixed was macOS by default shows the resolution they needed, but the capability was always there, you just had to use a 3rd party app in order to see and choose them until recently.
The issue of 4K monitors not being able to get 144hz is still persistent as the bugs within DSP are still unfixed. There's nothing new or changed to fix this just yet.
Apple has seeded beta 4 of 11.3 Has anyone tested it? https://www.macrumors.com/2021/03/15/apple-seeds-macos-big-sur-11-3-beta-4/
Oh yep! I tried it this weekend. Somewhat good news! I can confirm on my end that 11.3 beta 2 brings it back to where it was in 11.0. Where I can actually set my desired resolutions properly again (In this case, 5K but downscaled to a 4K panel), but DSC still isn't enabled so I can only see about 98FPS instead of my usual 144FPS.
It's certainly an extremely good step in the right direction.
Have you tried beta 4?
@fatheroates, Yes. I upgraded to Big Sur 11.3 beta 4 and tested it out. No change from that last post I made. 🙁
So just to reconfirm where we're at. Big Sur 11.3 fixes the issue that 11.1 and 11.2 introduced in that devices using DisplayPort 1.4 weren't working correctly, and often would only show lower resolutions than the panel actually supported. That is fixed, and we can at least reliably see 4K resolutions again.
However, Display Stream Compression still isn't enabled. So if your monitor relies on that technology to achieve its full resolution and FPS, currently you're still limited to the bandwidth of an uncompressed DisplayPort 1.4 stream.
So if your monitor is something like 2560x1440, you won't see any issues. But going beyond that (Such as 1440p ultra-widescreen, or 4K @ 144hz), it still doesn't work properly.
Considering the latest version of Xcode will only run on Big Sur now, when 11.3 leaves beta, I'm going to be forced to upgrade. I'm not 100% happy about this, but thankfully 98hz is high enough that I probably won't notice the difference in day-to-day operations.
@fatheroates, Hahaha I was wondering if someone would ping me to ask about beta 6. 🤣
Yes, I tried it. No, there was no change to number of frames I was getting (Still 99.88Hz). I already updated my radar with the results, but I still haven't heard anything from Apple.
Honestly, at this point, I feel like even if they figure out how fix it, they probably won't release it until macOS 12. I'm getting deja vu for when they held back support for the Xbox One Elite Controllers until they could announce it at WWDC. 😅
I already updated my radar with the results, but I still haven't heard anything from Apple.
FWIW Apple is looking into this issue. I got a reply for my radar a while back.
My setup of eGPU + Pro Display XDR x 2 works on Big Sur 11.3.1 perfectly, finally.
One of the XDRs connects to the W5700 with USB-C port, and the other connects to single DisplayPort with Belkin VR cable.
Both of the XDRs work on 6K resolution and 60Hz. Preference mode enabled, and brightness can be adjusted on Touch Bar.
My Pro Display XDRs are both on the latest update. The firmware version is 4.2.37
Someone also reported the update.