I'm having a problem now.
I swear I had this all working, and then the hardware sat for a while and some of the videocards moved around.
Now I get this terrible smearing when I move windows between logical (or real) gpus. Strangely, it seems like if I have multiple cards in, the smearing only happens between REAL gpus. If I have a single card, then it happens with logical gpus.
I have things configured right now so that instead of Twinview, I use multiple X screens + Xinerama. This only happens with Xgl running, which may be the culprit -- but it seems awful strange that I did not notice weeks ago when I first set this up. I'm linking a video of it happening on an 8800 GTX. It also happens with single and multiple sets of 9800 GTs.
If I start a window manager on the display that Xgl draws to, I can kind of make the drawing weird out by moving the Xgl window. That may lend credence to the theory that it is Xgl. I still post here in case anyone knows one way or the other whether it is a bug with Nvidia or Xgl. I am using the 180.60 drivers right now.
Does anyone have any ideas for solving this which may stem from adjusting obscure nvidia-settings options? I am also wondering if maybe it is an issue with Damage. I have tried toggling Render, Composite, and Damage, to no avail.
My video is here
This is for a school project, it is a big show stopper if I can't resolve this. I have one week