Compiz Fusion(fatal error)Composite extensions Nvidia

[alphamajestic]

I've just installed v3.4f on my pc with a nvidia 6800gs and now I can't get any 3D effects to work. When I click on the compiz fusion icon, all that happens is the screen goes blank then shows the mesage (fatal error: Composite extensions). So I take it that fusion isn't loading, but at other time I can get wobbly windows etc to work but never the 3D cube!
When I tried v3.4f live c.d everything runs fine,cube etc...
Also as the O.S loads I get the message vbox driver can't load. Also Emerald doesn't seem to work?
I'm using the default KDE desktop if that matters at all.
Any help would be great!!!

[wolfden]

have you ran the accel-manager ?
post your xorg.conf afterwards

If you don't use virtualbox, don't worry about it. It's not a crucial system file.