Comment 148 for bug 278318

The G45 chips only support textured video so the workaround is no good for them. The issue is fixed in the upstream driver:

http://cgit.freedesktop.org/xorg/driver/xf86-video-intel/commit/?id=67fef27f4b76490be085d232aba0ca9cbb3c5e59

I built from the 2.7 branch and the tearing went away. It would be great if someone could make a PPA of it.