Newbie DDR2 and PDSGE question

Apologize, I'm getting a PDSGE and I'm a bit fuzzy on the DDR2 standard.

I'm getting an 840 Pentium-D which has an 800Mhz FSB, but I see the top
end of the memory the PDSGE supports is 667.

I'm assuming the 667 is effectivly 1334 in speed?

Or am I mis-reading something here.
Bottom line, I'd like to make sure the memory I purchase is the most
optimal for the processor. I was considering
http://www.newegg.com/Product/Produc...82E16820227047

Again, apologize. I'm used to seeing the memory capability match the
FSB of the CPU in some way.

Thanks in advance.