So I received a Macbook Pro 16" M2 Max some days ago. I have been using a 2019 Intel machine for several years and struggling with external display support - on my Samsung G70A 4K 144 Hz display I was running into issues like getting a blank screen over Displayport and only image over HDMI if the display OSD is limited to HDMI 2.0 capabilities, even then only running at 4K 60 Hz.
When I got the M2, I was really hoping my display issues were finally resolved and I'll be able to use all the capabilities of any external display I might want to use. Sure enough, I was getting 4K 144 Hz over HDMI port, yay!
Except mysteriously HDR support toggle was completely absent. Now, this display is kinda garbage for HDR anyway so it's not a huge deal, but something I did not expect.
Well, turns out scaling affects if HDR support is available! This is such an utterly ridiculous premise to me! If I set the display to 1:1 scaling (1080p) or native 4K resolution, HDR toggle magically appears. If I set the display to scale to 2560x1440, HDR toggle is no longer available. The only way to get HDR is to reduce the refresh rate all the way down to 60 Hz.
Even plugging in my LG OLED TV I ran into the exact same problem - use scaling, lose HDR.
This is just plain insane. On Windows 11 the experience with this same monitor, using same cables (or adapters) over both DP and HDMI is that any scaling level allows toggling HDR support on and off and the display runs at 4K 144 Hz 10-bit color just fine.
Meanwhile the built-in display does not have any such issue. Why does it get preferential treatment? In system information it shows my external monitor rendering at 5120x2880 for "looks like 2560x1440", but the built-in display is reported as its native resolution no matter the scaling and also has instant scaling changes without blanking the display.
When I got the M2, I was really hoping my display issues were finally resolved and I'll be able to use all the capabilities of any external display I might want to use. Sure enough, I was getting 4K 144 Hz over HDMI port, yay!
Except mysteriously HDR support toggle was completely absent. Now, this display is kinda garbage for HDR anyway so it's not a huge deal, but something I did not expect.
Well, turns out scaling affects if HDR support is available! This is such an utterly ridiculous premise to me! If I set the display to 1:1 scaling (1080p) or native 4K resolution, HDR toggle magically appears. If I set the display to scale to 2560x1440, HDR toggle is no longer available. The only way to get HDR is to reduce the refresh rate all the way down to 60 Hz.
Even plugging in my LG OLED TV I ran into the exact same problem - use scaling, lose HDR.
This is just plain insane. On Windows 11 the experience with this same monitor, using same cables (or adapters) over both DP and HDMI is that any scaling level allows toggling HDR support on and off and the display runs at 4K 144 Hz 10-bit color just fine.
Meanwhile the built-in display does not have any such issue. Why does it get preferential treatment? In system information it shows my external monitor rendering at 5120x2880 for "looks like 2560x1440", but the built-in display is reported as its native resolution no matter the scaling and also has instant scaling changes without blanking the display.