If that doesn't help then check the refresh rate set in CCSM (package compizconfig-settings-manager) is correct (the same as your monitor refresh rate).
Other than that, I don't know. But it does sound like you problem is different to this bug so should be discussed elsewhere. If you don't find an appropriate bug then please log a new one.
Dave, if you're sure that tearing is not your problem but just a suboptimal frame rate, then I suggest you look at:
ATI and Intel: bug 763005
NVIDIA: bug 92599
If that doesn't help then check the refresh rate set in CCSM (package compizconfig- settings- manager) is correct (the same as your monitor refresh rate).
Other than that, I don't know. But it does sound like you problem is different to this bug so should be discussed elsewhere. If you don't find an appropriate bug then please log a new one.