It's no secrete that Nvidia and their developers have far better linux support than of ATI so no point arguing this people. Simply pointing this out helps no one and normally just turns into a flame war of company vs company.
With that out of the way more pressure needs to be applied to ATI and I think Valve is doping this well not just with ATI but a multitude of companies. Some won't even budge though look at the mess that Creative has created with their arrogant attitude out of the clear blue with complete refusal to even take a look at supported their new SoundCore3D chip (ca0132). However Linux Steam has been putting out some impressive accomplishments as well as their up coming Steambox. This could change the future of Linux gaming as well as support. *We can only hope)
Overall though anything new AMD/ATI cards have to offer having it in Linux right away is a rarity and even more so having it working in a stable way is even more rare.. However performance wise My 5970 card works pretty damn good in Linux in crossfire mode with most applications/games had very little problems with the exceptions of a few problems like GLSL shaders in games Like Aion which barely work in Linux under wine to begin with.
In the steam client I have great success with both companies so while ATI lacks in their driver support they make up for it in muscle which is a shame really that their developers just don't go at with a competitive approach even for simple things like crossfire support which needs an overhaul on how it's implemented, configured , and installed.
So rushing out to get the newest and best card and running it on linux don't expect to see huge margins of performance increased especially when they come from new features and or instructions because the applications themselves aren't written to take advantage of them which also holds true in windows. However it would help the Open Source community a great deal to have a reference to work with to help point out the glitches and bugs which will eventually in some near or distant future help the Open Source community.
This is true for Nvidia too however it seems that the linux developers at Nvidia seem to be more involved and perhaps just might be because of personal preferences there for roll out updates much more in tune to what the community is askign for
I'm quite sure they know that by now. Numerous threads about the drivers over the years. All initial Steamboxes will be powered by Nvidia, AMD later for obvious reasons. All new OpenCL gpu FAH cores can only be folded natively under Linux by Nvidia cards. Dev's developing Wine prefer using Nvidia ect. Pictures quite clear.
That said didn't AMD ask if everyone would rather see their Catalyst drivers improved or an open driver created ? Atleast I thought it was asked and an overwhelming majority responded for the latter. Maybe you could make a poll and ask if AMD should suspend their open drivers development, pull their devs until the cat's are up to par ?
I'm sure their dev's are spread thin right now OpenCl, Mantle, TrueAudio, PS4, Xboxone ect. While they finally posted in the black this quarter and hired a few for Linux their R&D simply can't match Intel possibly Nvidia too. I'm not sure how much
code is shared between Windows Linux and their Fireglide cards but I'm willing to bet it's no small task.
I hope they do give the beta a bit of luvin, with Rome:TT coming out and hopefully X:Reberth( Anyone know if/when?). BF4, IF/WHEN....(Personally don't think it will tbh)
Then there's Metro, I do seem to think that its AMD cpu's it dont like, again I suppose it could be driver related.
I think Metro's fine with the red team when you look around the different review sites when tested under Windows. So in a nutshell it is definitely the driver. On Steam, 4aGames have announced that they are working with AMD though so there will be a new beta driver likely before the end of the year.
During the AMA with AMD at Tomshardware, the AMD guy said that they will be releasing a fully stable (which I assume to be non-beta) and good driver for the AMD-spec SteamMachines. It is just that Nvidia has a head-start with Valve.
I have finished Metro LL on maxed settings with the R9-290X with CCC A.I. on; and enhanced AA using edge-detect. Worked smoothly but I can only surmise that it could've been even better and more smooth if AMD had a proper linux driver.
Lastly, watching --odgt and --odgc while playing games or running furmark; I can see the down-throttling quite a bit. With Serious Sam BFE I saw it reach below 800MHz!!! Not as much in Metro LL which I find peculiar as graphics fidelity with Metro LL is significantly better than Serious Sam. Perhaps Serious Sam uses the card like Furmark which doesn't look spectacular but does heat up the card. It did get hot in the room I was playing in though during that day due to warm wheather (late spring here down under).
So that said I have decided to upgrade the cooling; I'm likely to water cool it during the Christmas break or if a good dual-slot aftermarket cooler comes out for sale with good performance and acoustics, I may go down that path as well.