Originally Posted by Stephen Warren
ValdiskSS, rmmod/modprobe is the most aggressive way to reload the NVIDIA driver. If that doesn't work, a reboot is all that will. Sorry.
270.18 still exhibits the same issues - occasional hanging and "garbage" consistent with the screenshots posted when going fullscreen using vdpau. Syslog entries "NVRM: Xid (0001:00): 13, 0001 ..." are always present when the problem arises.
I've found that once the garbage appears, unloading & reloading the kernel module isn't enough. In those cases, suspend/resume has been as effective as rebooting, without losing any current X session(s).