I have the Corsair XMS pro series PC4000 like you, and also Kingston HyperX PC4000. Neither will allow me to run tighter timings at DDR400 speeds. That Ballistix seems to be the way to go.
<A HREF="http://service.futuremark.com/compare?2k3=3400555" target="_new"> My</A>
<A HREF="http://service.futuremark.com/compare?2k1=8268935" target="_new">Gamer</A>