nVidia dual head flicker

Does anyone else here run a dual-head nVidia config? I'm getting flickering or tearing on my second head. I used to get this on my 9.0 setup, but I fixed it neatly with an "Option HWCursor off" in my XFree config file. This fix isn't working on 9.1, though I don't know if I should be blaming the new kernel or a new version of X. In any case, it's annoying. Does anyone know something else I can try to get it fixed? Thanks, dk