AM2 and DDR 2 memory speeds

[mindwarp]

I was looking into purchasing a X2 3800+ for the AM2 socket. I noticed that it needs DDR2 memory, and that the specs call for PC6400. Is this correct? I read elsewhere on the boards that it could use lower speeds.

 

[n7]

You can use DDR2-533/667/800 (or higher if you OC).

 

[eplebnista]

http://forums.amd.com/index.php?showtopic=87112

 

[SonicIce]

I don't understand why the speeds seem so odd. Shouldn't it only need to be the same frequency as the HTT (200)? So why DDR2-667? Also why do you need higher speed memory for overclocking when you can use memory dividers?