Need A professionals advice

I am getting a new computer and i think of getting a good ram but which is better

1 gb RAM bus 800 CL5 or 1 gb RAM bus 667 CL4

note : iam planning on a dual channel

and iam planning getting an XFX sli motherboard

http://www.xfxforce.com/web/product/...ationId=998938


and E6600 C2d processor so plz i need really ur advice specially about the ram

You want the fastest memory the board will handle, which is apparently DDR2 800 (although it wouldn't surprise me to see a future BIOS flash enable the use of DDR1066 so it matches the FSB of the CPU).