Furry Technologists

I run the 6800 now, and while I can't comment on Linux, ROCm, etc. it's a totally solid card for 1440p - though I don't play the latest AAA titles, I finally get good frames at higher graphical settings in Planet Coaster. The 6800, 6800XT, 6900XT, and 6950XT are all in vaguely the same region of performance, mostly because they all have 16GB VRAM so it's all down to the number of CUs and clock rates.

If you do need every drop of power, you can snag an XFX 6950XT for ~$630 before tax if your case is big enough and power supply capable enough. I'd really only consider the 6950 if you're playing the latest AAA titles on ultrawide 1440p or 4K, though. Otherwise, you can grab either 6800 for up to a hundred less than the linked 6950, get plenty of VRAM and solid raster performance for a long while. The 6000 series has gotten the classic AMD Fine Wine^TM^ treatment, they aged pretty good all things considered.