Sandy Bridge graphics for media / home theater PC?

[finance_coder]

I was wondering if anyone out there is using Sandy Bridge (SNB) graphics for a Linux-based media or home-theater PC? (E.g., with MythTV, XBMC, or similar)

It seems that discrete nvidia graphics with the proprietary driver is the most popular setup for this kind of role. Particularly with vdpau, you can have a fully HD capable machine with a wimpy processor like the Atom (e.g. ION).

But personally, SNB looks like the way to go: you get a "real" CPU, and technically the graphics capability is there. I would think that the i3 and up SNB chips can do software decoding of any kind of HD stream you thew at it (although it would be even better to be able to use the built-in decoding hardware). All that, and idle power consumption on par with Atom (but without Atom's limitations).

I'm semi-envious of the Windows people---there's a long SNB thread on AVSForum, with lots of people talking about their low power, small, quiet and completely capable SNB home theater PCs. And it's all "just worked" from the day SNB was released.

So I'm just kind of wondering what the "state of the world" is with regards to SNB graphics on Linux. Just from skimming Phoronix here, it looks like it's worked acceptably for a while. But how hard is it to get to an "acceptably working" state? Do any distributions support it out of the box? Or will it require manual compiling and configuring of kernel, driver, libraries, random X components, etc?

In other words, how close is it to having ease-of-use parity with Windows? I'm not so much concerned with absolute performance, just that it performs acceptably and most importantly stably in a HTPC context (e.g. playback of high-bitrate HD content).

Thanks!

[Kano]

Be sure that you have got current:

http://cgit.freedesktop.org/vaapi/libva/

and

http://cgit.freedesktop.org/vaapi/intel-driver/

and vaapi should be fine with xbmc on snb. At least much better than using the xvba-video wrapper for amd.

[finance_coder]

So based on that response, it sounds like it's still not in the "just works" category.

I know I rambled a bit in the original post, but what I was really getting at is: is SNB graphics on Linux as easy to use as it is on Windows? I.e., with Windows, you don't have to do anything special. Looks like the best SNB graphics support on Linux is still "bleeding edge", and you need to jump through some hoops to get it working correctly.

What I really want is a low power MythTV frontend, without spending a lot of time futzing with getting it to work. I'm half-way there now with a discrete nvidia GT 430 (I consider the nvidia video to generally "just work" in Linux). But I'd like to ditch the discrete video card, so I can save on power consumption, necessary case cooling, and go with a smaller case overall... but not at the expense of spending a lot of time building drivers and/or libraries. I don't even care about the hardware video decoding---just want a display that works reliably, and I'm happy to let the CPU do software-based decoding. My goal is something like this build. Less than 15 Watts idle power consumption yet fully capable for media duties (and would "just work" on Windows).

Thanks.

[zog6]

I am using an i3-2100t CPU with an intel DH67CFB3 motherboard for a home theatre PC.

It's not totally bleeding edge (I haven't had to compile a kernel) but it took a little bit of fiddling with libraries to get it working.

I'm using the Xorg edgers PPA to get the latest Xorg stuff, had to patch mplayer to get VAAPI (and the instructions dont work out of the box with the paths the PPA debs install to). I havent got the GUI version of the patches mplayer working, just the "command line" version so I need to operate it via the hotkeys to play movies.

I'm using Xubuntu as the loungeroom PC gets a lot of normal PC/web usage as well as watching vids.

Works pretty well except there is the occasional tearing or ripple effect on playback of videos.. not load related as the system barely breaks a sweat, it doesnt wreck the movie experience but is an annoyance.

So nearly there.. but not perfect, but usable.

[finance_coder]

I am using an i3-2100t CPU with an intel DH67CFB3 motherboard for a home theatre PC.

It's not totally bleeding edge (I haven't had to compile a kernel) but it took a little bit of fiddling with libraries to get it working.

I'm using the Xorg edgers PPA to get the latest Xorg stuff, had to patch mplayer to get VAAPI (and the instructions dont work out of the box with the paths the PPA debs install to). I havent got the GUI version of the patches mplayer working, just the "command line" version so I need to operate it via the hotkeys to play movies.

I'm using Xubuntu as the loungeroom PC gets a lot of normal PC/web usage as well as watching vids.

(...)

So nearly there.. but not perfect, but usable.

That's encouraging!

Works pretty well except there is the occasional tearing or ripple effect on playback of videos.. not load related as the system barely breaks a sweat, it doesnt wreck the movie experience but is an annoyance.

I wonder if that's a software issue, or related to the fairly well-known "24p bug" with the hardware itself? (Google "sandy bridge 24p bug" for plenty of info.)

Anyway, thanks for posting your experiences!

[zog6]

That's encouraging!



I wonder if that's a software issue, or related to the fairly well-known "24p bug" with the hardware itself? (Google "sandy bridge 24p bug" for plenty of info.)

Anyway, thanks for posting your experiences!

I wasn't aware of that bug, thanks for bringing it to my attention! I have noticed what looks like that occurring as a slight ripple on slow panning shots. But I've also seen more apparent tearing effects that definitely aren't this bug, more on faster action shots, and only on certain video files so perhaps certain encodings trigger it more - I'm hoping this is a software bug that will get fixed over time. I haven't sat down and documented it with a test file that repeatedly triggers it however.

I'd actually got a case for the PC (isk300-65) with room for a low profile PCI-E video card, so I can drop in an nvidia 210 - but it turned out the 65 watt laptop style "brick" power supply wont play with my nvida 210 card.. so right now I'm just accepting it being a bit iffy sometimes, if the bug doesnt get resolved I'll get another case/power supply and drop in the nvidia card.. but I'm hoping the software gets more refined as an i3-2100t is otherwise an excellent little low power use, but powerful media PC (optical audio out, HDMI, quiet!, low power use).

[LeonM]

I'm running an 2100T H67 setup as a HTPC for quite some time now, always used bleeding edge mesa, DXX, vaapi and XBMC etc.

I must say, running it as a HTPC with VAAPI enabled in XBMC is pure awesomeness, the CPU really doesn't do anything (approx 1% load). That makes the whole setup very quiet, and it uses very little power (approx 25W!). It is really elegant.

However, and I really hate to admit it... if I were to build a new HTPC now, I would not use a Sandy Bridge CPU.. The lack of hardware support for 23,976 FPS (known as the 24p "bug") just spoils everything! Currently IMO the best solution for a low power HTPC solution is the AMD Fusion platform. I recently build a Fusion based XBMC for a friend with a Foxconn NT535 barebone, and that was a truly sweet setup.

The Ivy Bridge CPU is supposed to have 23,976 FPS support, and as far as I know it is compatible with H67 motherboards, so I might just upgrade to Ivy Bridge next year..

[Kano]

I think that 24000/1001 hz support is overrated. I watched all my movies with 60 hz and it was never problematic, not even pal (25 fps) ones. My monitor does not support 24 hz as it is a 1920x1200 tft. If you need to drop 1 frame every 1000 frames (41.67s) it does not sound much for me, it is just that you would need a stop watch to recognise it.

[LeonM]

I think that 24000/1001 hz support is overrated. I watched all my movies with 60 hz and it was never problematic, not even pal (25 fps) ones. My monitor does not support 24 hz as it is a 1920x1200 tft. If you need to drop 1 frame every 1000 frames (41.67s) it does not sound much for me, it is just that you would need a stop watch to recognise it.

As I said, I hate to admit it, but it does spoil the show. Maybe the extra frame is less obvious on a TFT display due to the refresh time, but on my LED TV it is really annoying, even my GF complains about it

It gets even worse when you watch a 3D movie with active shutter glasses...

BTW, the frame is not dropped, but duplicated, as it tries to keep the video stream in sync with the audio stream en subtitle stream. If the bitrate of the audio stream could somehow be increased slightly, you could just play the movie at 24 or 25 Hz, without ever noticing it. The film would just be a couple of seconds shorter This is however not possible, as the encoder and DAC's of your receiver/soundcard don't support that.