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Revision as of 12:37, 9 March 2013 by Dhead (talk | contribs)
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Questionable Statements

"Radeons from HD 2xxx to HD 6xxx ... (for example, powersaving is still in a testing phase)." I do believe this is now functional, from using my HD6770 with power_profile and the featureMatrix represented on Any objections to removal? T1nk3r3r (talk) 18:22, 6 February 2013 (UTC)

Is there any offical release note /commit log about powersaving support exit testing phase ? -- Fengchao (talk) 09:31, 7 February 2013 (UTC)
Excellent point. I think I can investigate that later today. Although the table on showed most features functional across the board. This may have happened months ago. T1nk3r3r (talk) 19:03, 7 February 2013 (UTC)
I don't have time to cherry-pick through the commit logs. I skimmed through 2012. However, this page shows the options for powersaving, and the table clearly shows functions are complete for all but the oldest cards. On the flip side, where is the reference proving the original statement? T1nk3r3r (talk) 20:57, 8 February 2013 (UTC)
Then the testing phase statement could be removed. --Fengchao (talk) 12:54, 11 February 2013 (UTC)

KMS -- do we have to do anything at all to enable it?

The KMS sections says it's on by default, should we even have to put radeon in MODULES any longer? If not, the intro to that section should probably mention that "you can skip the rest of this section if 'dmesg|grep modesetting' shows 'radeon kernel modesetting enabled'.

(rc.conf/MODULES are deprecated with systemd) Thinking about it, I don't explicitly recall having to enable it for the default ARCH kernel. The late start section may indeed be rendered redunant. Can anyone confirm this on a fresh install? T1nk3r3r (talk) 18:45, 6 February 2013 (UTC)
From this page, it is stated that the current behavior is to autodetect. So as long as the module is available and the hardware is there, it will load without intervention. It only remains to be stated when this started -- for now we can simply say: currently. Leave a link to xorg? T1nk3r3r (talk) 21:06, 8 February 2013 (UTC)

KMS Early

I don't know how others feel about this, but my preferred setup is to put options radeon modeset=1 in modprobe.conf and then to include modprobe.con along with the radeon module in mkinitcpio.conf. This way KMS is enabled once for both early and late start. Also, in the event of problems, radeon.modeset=1 can still be added as a kernel option to the bootloader. --piezoelectric

The bigger question here is: How early is Early? If I'm not mistaken: boot options come first, then initramfs, then modprobe.conf once the final root filesystem is mounted. If it is enabled at boot, any other toggles may be rendered pointless. This may only be applicable if firmware needs to be compiled into the kernel (newer cards). On the other hand, see parent section here. T1nk3r3r (talk) 18:45, 6 February 2013 (UTC)

Enabling video acceleration

~/.bashrc is the wrong place for setting this environment variables. This file is not consulted when starting i.e. firefox from the gnome shell. As it is a hardware dependent setting that is reasonable for every user on this box, i created a file in /etc/profile.d/ to accomplish this.

Setting this variables makes a difference when using flashplayer for youtube videos. When set, flashplayer reports accelerated rendering enabled at home with my ati hd3200 onboard graphics and rendering is faster in full screen mode.

It works now no more worse than under windows.

Radeon vs. Catalyst


The ATI and Catalyst pages state that Catalyst performs better for 3D. As most of you may have experienced, the Catalyst driver is clunky and very badly optimized for Linux. Gaming performance is usually worse than on Windows. Catalyst and Nvidia drivers do not uses Unix interfaces properly (Linux kernel and Xorg), a big part of it is just a bunch of hacks. See what the nouveau folks think. It's probably a matter of syncing development between different platforms, so adapting the driver as less as possible from Windows is probably more profitable. The lack of respect for interfaces has one major issue: the compatibility with Xorg and Kernels is extremely fragile. Besides, a lot of features or simply not reliable (or at least a real pain to setup) with these drivers, such as dual head / external output, custom kernels, hibernation...

It would be a great relief for the Unix communities to finally have a free, full-featured and top class 3D graphic driver.


AMD did a very good thing when they decided to release the specs of their cards. FOSS radeon driver is now lightyears beyond nouveau in term of OpenGL implementation. The FOSS radeon driver seems like the ideal future of Unix graphics to me.

Since version 9.0.* from late 2012 and January 2013, OpenGL implementation has moved several steps forward as you can see on the feature matrix. In fact, I've tested several games (native or Wine) and radeon performs much better than catalyst most of the times.

For performance and Unix-frendliness, I suggest we should encourage Unix users to choose radeon over catalyst. Too many people are held up in their switching-to-Unix because of the terrible, infamous catalyst, even if all they need is average 3D graphics.

Since this revolution is brand new, it requires support from the community. We also need concrete data that states the progress, the support and the performance of radeon compared to catalyst.

I suggest we create a benchmark page for that. Should we create a new page? I'll begin it below for now, but we shall move it in the future.

--Ambrevar (talk) 12:07, 6 February 2013 (UTC)

A benchmark page could be informative, especially for newcomers that are having a difficult time making up their minds. AMD is actually shifting support from Catalyst to radeon drivers. They had hired two bodies to work on the radeon driver. But then I came across this:
I just found this:
Regardless, there has been a lot of headway in the last four years. I recently tested some games on vanilla Wine and performance was considerable.
When I came to Arch, I was using Catalyst. I was a pain to setup and maintain. I was since persuaded by a Wine developer to switch to the radeon driver, as it is much easier to debug and submit patches upstream for either Wine or Radeon. Not to mention Catalyst only ever "officially" supported Ubuntu, SUSE, and RedHat.
Drop a line to the Catalyst talk page? T1nk3r3r (talk) 17:27, 6 February 2013 (UTC)
I think the message in the introduction is clear: If unsure, try the open source driver first, it will suit most needs and is generally less problematic. -- 09:37, 7 February 2013 (UTC)
Sure, but the previous paragraph clearly tells 'if you want 3D performance, go for Catalyst', which is not very true anymore. --Ambrevar (talk) 09:43, 7 February 2013 (UTC)
I agree. So we just need a clear statement from a benchmarking website that supports that. Preferably something recent.
I will not question the removal of dubious statements, so long as that point is made clear in the edit summary. T1nk3r3r (talk) 19:00, 7 February 2013 (UTC)


To be continued.


Worth to mention that the powersaving is related to overheating issues. With the default powersaving off my laptop's graphic card, Mobility Radeon HD 4650, overheating causing the system to shutdown. Changing the setting to mid solved this issue.Dhead (talk) 12:37, 9 March 2013 (UTC)