DDR2 800 only getting 400 out of it? This is weird! HELP!

So I have 2GB's of Corssair XMS2 DDR2 800 and I have set my timing in my BIOS to 4-4-4-12 and 2.1v which Corssair actually recommends. I have had it that way for a long time, but just recently I checked my CPU-Z under the SPD tab and it says "MAX BANDWIDTH": PC2-6400 (400 MHz). Below that is says Timings Table and under the Frequency it says 400MHz.

Does this mean I am only getting 400 MHz out of my 800 MHz RAM? How do I fix that?

My Specs:
Core 2 Duo E6600 3GHz
EVGA 8800GT Superclocked (Core 700, Mem 975)
2GB Corssair XMS2 DDR2 800 (4-4-4-12)
700w OCZ GamerXStream PSU
eVGA 680i Mobo
320GB Hard drive 16MB cache 7200RPM
Windows XP

^ yes.
And ask yourself: How would memory at 800MHz real (1600 effective) possibly speed up your overall bus speed? Your link is only as fast as the slowest connection, which would be the CPU FSB (333MHz).

Ahh thanks guys. Good to know.