I had some issues on the weekend with my HTPC playing some new gaming titles, I found I was getting really low frame rates even when droping all settings and resolutions, the system is dual bootable so rebooted to Windows and the games ran fine in 4k and with high settings.
I booted back into Bazzite and I found some seriuous issues with the GPU clock and reported power.
My system is:
Ryzen 7 5800X
32GB Ram
RX 6900 XT
Asrock X570 Motherboard
1TB NVME Drive
1200w Corsair Power Supply
Full open loop liquid cooling (Both CPU and GPU)
First thing I noticed, is the GPU clock is locked to a max of 1500mhz but the card is reporting 340w consumption in Gamescope, I went and enable LACT and tried to manually set the clocks and set the TDP to max and run furmark in the desktop mode, and the card reports 381w and 2Ghz max clock, so something is very wrong here.
In Windows, my GPU runs default 2550mhz and only pulls 250w, and even when I max all the power, and OC to 2900mhz, it runs 2880mhz and still does not pull anywhere near 381w.
Not sure what is going on, but there is some really strange behavior, I didnt notice this in the past, as the games I was running hit 60fps locked as they are older titles, but now I’m running some newer titles, I am seing the card struggle, but only in Bazzite, and this GPU clock speed thing is the reason why.
The CPU is performing as expected, hits just south of 5ghz all core load, and my temps are well under 50C under full bench marking, as the cooling system is massive, its an extremely thick 360mm rad with 6 Noctua fans in push pull configuration with dual D5 pumps, the GPU is the XFX MERC Edition with factory installed EK full cover water block.
If I need to provide some logs or if there is a full benchmark I can run specific to Bazzite let me know as I would like to resolve this, I hate using Windows when sitting back on the couch playing my console like games 
Also, I have tried both BIOS on my XFX card, as I think one was supposed to unlock higher TDP, but it makes no difference under Bazzite.