I hope you can help with a problem I've always had (2-3 years now) with my NV card. I'm afraid this is a bit of a double post as I've posted pretty much the same thing to the Arch linux forum
before being directed here.
Ever since I've had my current computer over 2 years now I've had quite considerable tearing video on my screen whenever I have any large degree of movement on my screen (watching videos, dragging windows or turning my head in games).
I decided to look into it and it appears that VSync is designed to remove tearing like this where the tearing is the result of a mismatch between your Monitor Vertical refresh rate and the rate that your video card is updating it (in my case a Gigabyte GeForce 8600 GTS Silent Pipe 3).
So I've tried experimenting with VSync to see if I can remove my tearing problems. I've found that I can't but I've found something interesting. With OpenGL VSync off I get lots of little tears - while turning in an opengl game - however with VSync on I get one near continuous tear about a 5th of the way down the screen. No matter what the OpenGL or Xv VSync options I seem to get lots of little tears when dragging windows around (at the moment in xfce with no effects).
I've also tried enabling triple buffering on my card in xorg.conf which hasn't changed much. I thought that maybe VSync was mis-detecting my refresh rate slightly which is why I was getting a near constant horizontal tear. So maybe I can find some way to tweak my refresh rates for VSync by hand??? If this is the case then I've noticed that my refresh rate on my monitors OSD changes with the screen resolution so any tweak would have to be able to set for each resolution.
I'd appreciate any advice you can give me to beat this once and for all.
P.S. My monitor is a Digimate L-1715 and I'm running the NVidia drivers 195.36.15.