How to force 10-bit color through CRU

[Noatmo]

Hey,

So, I recently picked up a Corsair 32UHD144 and I'm using HDMI to avoid the need for DSC. Using HDMI the monitor allows me to select 8 and 10-bit color at 120Hz, but only allows me to select 8 and 12-bit color at 144Hz. Is it possible to force a custom resolution and bit depth through CRU or Adrenaline? If it allows a 12-bit signal, I don't understand why it couldn't also accept a 10-bit signal as a 12-bit signal would require more bandwidth.

[ToastyX]

If 10 bpc is available at 120 Hz, then it should be available at 144 Hz unless the color format is different. The 4:4:4/4:2:2 color formats are in the HDMI data block, and 4:2:0 color formats are in the HDMI 2.x data block. If 10 bpc is already enabled for all formats, then it's a driver limitation. Maybe disabling 12 bpc will allow 10 bpc. There's no way to specify a color format for a specific resolution.

[Noatmo]

(08-11-2023 04:40 PM)ToastyX Wrote:  If 10 bpc is available at 120 Hz, then it should be available at 144 Hz unless the color format is different. The 4:4:4/4:2:2 color formats are in the HDMI data block, and 4:2:0 color formats are in the HDMI 2.x data block. If 10 bpc is already enabled for all formats, then it's a driver limitation. Maybe disabling 12 bpc will allow 10 bpc. There's no way to specify a color format for a specific resolution.

So... Yeah. Here are the HDMI pages for the Corsair. Anything look amiss here to you? I don't see anything wrong, but I'm also not very familiar with this.

Also, this is running on an RX6800XT using the latest version of adrenaline. It's connected using a certified cable.

[ToastyX]

It looks fine. I think it's a driver or GPU limitation. 3840x2160 @ 144 Hz requires DSC for 12 bpc but not 8 or 10 bpc, so maybe the issue is related to DSC in some way. Disabling "DSC 1.2a" in the HDMI 2.x data block should disable DSC, which might allow 10 bpc to work normally.

[Noatmo]

(08-14-2023 01:42 AM)ToastyX Wrote:  It looks fine. I think it's a driver or GPU limitation. 3840x2160 @ 144 Hz requires DSC for 12 bpc but not 8 or 10 bpc, so maybe the issue is related to DSC in some way. Disabling "DSC 1.2a" in the HDMI 2.x data block should disable DSC, which might allow 10 bpc to work normally.

Well, that sucks. Disabling DSC didn't fix it either.

I'm kind of stuck here... It's an absolutely beautiful monitor, but I really hate the idea of compressing the data stream straight out of the GPU. I know VESA claims that it's, "visually indistinguishable" from an uncompressed CVT-RB stream, but I have a hard time believing that. Besides, spending thousands of dollars on GPUs and monitors just to compress the crap out of the image anyways seems wrong on principle.

Maybe I'll just return it and go with a lower res monitor. Thanks for trying to help, though.