4k60 RGB 444 over HDMI?
Bazzite newbie here, with limited other Linux experience (mostly Ubuntu), and I'm having a heck of a time figuring this out. From my understanding, RGB 444 at 4k120hz is impossible over regular HDMI on an AMD card because of HDMI forum nonsense not allowing full HDMI 2.1 bandwidth on an open source driver. But I'm running 4k60, and I still don't seem to be getting FullRGB 444 with Bazzite, in either Desktop or Gaming mode (can't speak to other Linux distros. Ubuntu doesn't seem to give me any colourspace settings when running off a USB drive, and I don't want to install it again). At best it looks like YCbCr 4:2:2, which is better than 4:2:0, but still not great.
In desktop mode changing the colorspace setting between Full and Limited does absolutely nothing (also turning on HDR in Desktop Mode doesn't turn HDR on. Turning it on in Gaming Mode does, so I'm forced to assume the Desktop Mode display settings are just fully broken). Doing a comparison of some images between my Windows boot and Bazzite desktop, the colours are definitely more crushed in Bazzite than in Windows, and the same bears out with actual chroma test images. It's hard to check test images under Gaming mode, but the colors seem to be even more crushed there. I've tried turning on 'force composite' in the developer options and that doesn't make much of a difference. Disabling colour management in developer options in gaming mode makes everything a lot darker under SDR, but that's not a great fix, and still doesn't match Windows. I've also tried dropping my resolution to 1080p, but nothing changes, colour wise.
Am I missing something? I'm tempted to buy a DisplayPort->HDMI 2.1 adapter, but I feel like if things aren't working at 1080p then I'd most likely just be wasting my money.
Specs wise, my system is a Ryzen 7900x, Radeon 7900 GRE, 32 GB RAM, Gigabyte Aorus X870 motherboard
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Well, I apparently made a horrible mistake and tried plugging the HDMI directly into the TV instead of the receiver, which didn't make any apparent difference, but then when plugged it back into the receiver it switched the colourspace to either RGB Limited or YCbCr 4:2:0, and I've tried everything I can think of to make it go back, to no avail. So I guess I've gotta nuke the whole partition and reinstall Bazzite from scratch. Awesome.