Display Stream Compression not working with Third Party Monitors

Number:rdar://FB8898101 Date Originated:11/15/2020
Status:Open Resolved:
Product:macOS - Quick Look Product Version:11
Classification:Graphics Reproducible:Always
I'm using an ASUS ROG Strix XG27UQ gaming monitor with my 16" MacBook Pro. The monitor supports 4K at 144Hz using Display Stream Compression technology.

On macOS 10.15, everything works as normal. I am able to drive the monitor at 4K with 144FPS.

Unfortunately, when testing out Big Sur on a separate partition, I discovered that macOS 11 reports that it can only drive the monitor up to 98Hz. This would seem to imply that macOS doesn't recognise the monitor as being DSC capable.

This seems to be a regression on Big Sur's behalf. I'd rather not diminish my user experience when upgrading to Big Sur, so I hope this can be resolved quickly.

Thank you!


I have same issue, too.

After updating to Big Sur, extra display is not working well only in connecting USB-C. It can select onIy 30Hz. Also, sometimes it dose not recognize the signal from monitor. I'm using LG32ud99. Hope it will be fine.

By one.hope.one.love at Dec. 19, 2020, 8:21 a.m. (reply...)

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