Nvidia Ion, Ubuntu Karmic and Composite
I've tried posting in forums and searching on google, and even posting a bug to Nvidia. All to no avail so far - maybe YOU can help? ;o)
I have an Nvidia ION machine, running Karmic. I have the 195 drivers installed. I'm trying to watch 720p video in H264 encoding. If I turn off composite in xorg.conf, all is good. It looks fantastic, and I'm very happy.
However, I'd like to use composite, and the various docks and effects that it allows. There's lots of graphics power sitting untapped in my ION because I can't use composite. What happens if I turn on composite in xorg.conf? I get a tear in videos about an inch down my 720p TV screen, and nothing I've tried can get rid of it. [Yes, I have VBlank set in Compiz, and in gl and xv in nvidia-settings]
Now, I've read up about this, and it seems to be caused by the switch from "overlay" presentation (used when composite is off) to "blit" presentation (used when composite is on). Overlay cannot tear, but blit can. But this "tearing in blit mode" was meant to be fixed in the 185 drivers. So why do I, and a few other people I've read about on the web, get a constant tear 30-50 pixels down the screen with the 190 and 195 drivers still?
I'm happy to post anything you think will help debug this. Or if you know it is still an unfixed bug in the latest drivers, then let me know so I can just track the bug and wait 'til it's fixed (or go get some hardware that can do it). But not knowing what's causing it is driving me crazy.