The 'Ol GPU Debate

[theflamingchicken]

I'm building a new computer that will run Ubuntu Linux as it's primary OS. I plan on dual booting Windows to play games, and with all the AMD / ATI Linux headway, I thought I'd buy their GPU to show some support. But before I do, I need to make sure that the ATI drivers (preferably the open source ones for an HD 48x0) can support:

1. Widescreen Monitors (specifically 22inch widescreens)
2. Dual Monitors (absolutely necessary)
3. Multimedia (movies)

Compiz and all that 3D stuff isn't too important for me. I know that in the near future, the ATI drivers will be much better, but for right now, I just need something rock solid. Am I better off going with nVidia?

[CrystalCowboy]

Dual widescreen monitors should be no problem at all.

I'll let someone else respond about multimedia.

[sastraxi]

With an X1400 mobility and the "ati" driver, textured video is working very nicely, even when under 3D (as in... XV redirects correctly and you can make the window semitransparent and all that jazz). Good performance though I haven't tested anything HD. 3D crashes very often for me, though.

As for widescreen support, I can't get the "ati" driver to do anything Xrandr related. It crashes the X server. I am on intrepid, however.

[Zhick]

Multimedia (movies)
Not yet there on anything >= Radeon 2XXX. There's zero acceleration, so you'll need a beefy cpu for HD videos. Bridgman says they're already working on it though.
On 1XXX Series Radeons 2d and videos are working very nicely, except there's no vsync (except in an experimental branch).

[theflamingchicken]

I'm not very well read in the whole HD movie department, but I am getting a pretty beefy CPU in this new setup. Will I have any trouble with normal DVD rips and stuff? Or aren't the radeonhd drivers able to handle that? I'm not into any video editing or anything, just need to be able to watch some movies.

[Zhick]

Just to give you an idea of what's possible without acceleration: I'm able to watch 720p videos with a xine-based player (kaffeine to be precise) using Xshm (=software-rendered) as video-output with ~50% (~30% Kaffeine + ~20% X) CPU-usage (according to top, so 25% when you take the second core in account) on my C2D E6600@3Ghz.
So 720p should be no problem on most current CPUs. I haven't tried 1080p yet though.

[theflamingchicken]

Awesome. That's really all I was really concerned about. So long as the ATI drivers (open source and proprietary) keep progressing at the rate they've been going during these past few weeks, I think I'll be in good shape. Any word on when accelerated video should arrive?

[RealNC]

Just to give you an idea of what's possible without acceleration: I'm able to watch 720p videos
...with unbearable tearing.

[Zhick]

...with unbearable tearing.
I actually didn't notice any tearing on big buck bunny. But yes generally there will probably be tearing until Xv + vsync are properly implemented in the open drivers, as I already mentioned.

Any word on when accelerated video should arrive?
I'd guess two months but that's just a guess. Bridgman could shed some light on this but he probably wont.

[theflamingchicken]

So we have to put up with video tearing until the drivers are "properly implemented" or is this just an issue with Compiz / etc? Are there any fixes for this besides just waiting for it to be finished?

[bridgman]

I'd guess two months but that's just a guess. Bridgman could shed some light on this but he probably wont.

Right. I'm not going to make any more estimates until we have the driver stack drawing the first textured triangle. Getting to that point has taken a lot longer than expected.

[Zhick]

So we have to put up with video tearing until the drivers are "properly implemented" or is this just an issue with Compiz / etc? Are there any fixes for this besides just waiting for it to be finished?
Only way to get vsync on ATi cards right now is fglrx + opengl video-output + enabled vsync in amdcccle.

[theflamingchicken]

Only way to get vsync on ATi cards right now is fglrx + opengl video-output + enabled vsync in amdcccle.

And this works alongside my other "ultimatums" (that is, dual screen and widescreen)?

[paul]

With an X1400 mobility and the "ati" driver, textured video is working very nicely, even when under 3D (as in... XV redirects correctly and you can make the window semitransparent and all that jazz). Good performance though I haven't tested anything HD. 3D crashes very often for me, though.

As for widescreen support, I can't get the "ati" driver to do anything Xrandr related. It crashes the X server. I am on intrepid, however.

Did you try this in xorg.conf:

Option "GARTSize" "32"