now a days ddr2 667 on intel = ddr 400 on amd
when amd will shift to ddr2 if intel carries out with its netburst architecture ddr2 on intel will be easily overcomed by ddr2 in amd even it will be rock solid.
it doesnt make difference if ur using nforce 4 sli intel edition its the memory controller on amd its on chip on intel not so whatever it happens amd is way ahead of memory with intel