The M2 Max and Ultra Mac Studio finally comes with HDMI 2.1, bringing it up to par with the M2 Pro Mac mini and MacBook Pros. But does it have the same limitations the other computers do?
I’ve made several videos previously testing the limits of how well HDMI 2.1 worked on the 14″ MacBook Pro and Mac mini with my 48″ LG C1 TV that I use as a monitor. I was eager to see if any there were any improvements with the Mac Studio. After all, I didn’t have an M2 Max chip to test before.
Mac Studio Limitations
When I booted up the base model M2 Max Mac Studio, it came preloaded with macOS Ventura 13.4, which means I couldn’t test to see if the macOS 13.0 ability to select higher resolutions at 120Hz and HDR enabled to the point where it green screened to death would still work.
However, I quickly discovered that the M2 Max Mac Studio doesn’t seem to be any different from the M2 Pro Mac mini in what resolutions and refresh rates are supported. At the default scaling of 1920×1080, which is exactly half the width and height of 4K UHD, you can go up to 120Hz and enable HDR. However, going up to 2560×1440 means you can only go up to 100Hz and still have HDR on. If you set it to 120 Hz or variable refresh rate, the HDR option disappears.
I still believe this is something that Apple could improve if they wanted to, but also believe that it’s not high on their priority list.
Using a utility that lets you set custom resolutions, I found that the maximum resolution that supports 120 Hz and HDR is 2432×1368, which is 127% of the default 1080p scale factor. I like to use more round numbers, so I decided to use my Mac at 2400×1350 resolution, which is 125% of 1080p scaling.
Of course, my preferred scaled resolution is 1440p, but that would mean either doing without HDR or lowering the refresh rate to 100 Hz and not using variable refresh rate. Since 100Hz is not a clean multiple of common video refresh rates (other than 25p), I decided not to use this.
LG C1 VRR Info
Regardless of the scaled resolution, we can see from the LG C1 VRR info that the Mac Studio is running at 2160p 120Hz with variable refresh rate support, and YCbCr 4:4:4 10-bits per channel.
HDR Turns Off
One very annoying issue I ran into, however, is that if the TV is turned off for a while, when I come back and turn the TV on again, the Mac may have switched HDR off instead of remembering that it was on. And since macOS seems to lack a hotkey shortcut for toggling HDR by default, I need to open up display settings to turn HDR back on.
Overall, the HDMI 2.1 implementation in the Mac Studio seems to work very similarly to the Mac mini and MacBook Pros. I guess that shouldn’t be a surprise since they are all M2-generation chips.
Hopefully Apple can make higher resolutions and refresh rates work with HDR in the future. Until then, we’ll have to live with these limitations.