I'm also affected by this. I won't post my Xorg.log because I don't feel that it provides any new information as it looks basically identical to Colby's. Instead I've attached StepMania's crashinfo.txt which contains some helpful debugging info.
** Attachment added: "crashinfo.txt" http://launchpadlibrarian.net/31803861/crashinfo.txt -- xserver crashes after running StepMania for a few minutes https://bugs.launchpad.net/bugs/400463 You received this bug notification because you are a member of Ubuntu-X, which is subscribed to nvidia-graphics-drivers-180 in ubuntu. _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : [email protected] Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp
