x11 Video playback pauses

Check your drives and also make sure your caching enough of the video. Sometimes the defaults are too low. Also sometimes the default driver isn't the best one. If you can use dri then don't use the X11 codec. Use OpenGL or something else. Try all you have and see which one performs the best.

Which media player are you using?

It could be your sound. Pulseaudio does this sort of thing to me all the time, but if I switch to using ALSA directly everything works fine.

I've had quite a few issues with PulseAudio, video playback was one of them. Open up a terminal and type:

sudo killall pulseaudio

See if that helps.

x11 isn't a codec, its a video driver. Mplayer can use a bunch of different drivers. Do

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to see what ones are availiable, then select one and do

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to use it. gl/gl2 (OpenGL) may work, you could also try xv.

Opengl will flicker even more. The newer ATI drivers (9.2) resolve the flickering with video playback and Xv (beware that it sometimes crashes X).

well, the new ATI drivers cause my system to not display anything at all past the Ubuntu splash. I had to disable gnome so I could get into the text only interface, install envyng-core and let that install the drivers for me.

The drivers just dont like my 3870 X2 I guess lol

Like I said Radeon doesn't get along well with Linux. Get a chip nVidia card and you will be amazed how easy and nice it is

First: It's silly to recommend him to switch cards given that ATI hardware is well supported in Linux.

Second: I haven't been paying attention to Linux Crossfire support so I had no idea the HD3870X2 was even supported; given that you already had the driver working it's obvious that it is.

Third: It's best to install the driver "manually", meaning run the ATI installer. Just remember to initialize the module at the end;

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I never had anything but trouble with ATI's drivers on Linux, with their higher end cards. Interestingly, they seem to work better with onboard GPUs (e.g. laptops). So I have nvidia.

Well, I know that ATI driver support for Linux sucks. I also know that I'm not swapping to nVidia until I get the spare cash to drop on a card that will be an upgrade from my 3870 X2.

But, here's my understanding:

the x11 driver makes your CPU render whatever is being displayed, right?

If that is true, then why am I getting intermittent pauses while playing avi files? My CPU has more than enough umph behind it to render a 2d display. Is there some option I need to enable to fix it?

Not sure if that is correct or not about the x11 driver. Maybe it's just native Linux facility still driven by your graphics card. Have a link?

What media player are you using? How much cache? What about the stuff I asked at the beginning?

I never heard of SMplayer. Do you have another player (mplayer, VLC) to compare it to?

X11 uses the CPU to render. If video is choppy it's something else and not the GPU. Did you try killing Pulseaudio (or switch to using ALSA directly)?