Comment 39 for bug 223238

You can read interesting things that might help you here: http://www.nvnews.net/vbulletin/showthread.php?t=118088
You are using driver version 169, I'd advice to at least install a later driver via envyng.
For me the command mentioned in above thread made everything very workable:
"~$ nvidia-settings -a InitialPixmapPlacement=2"