Currently Being ModeratedJan 31, 2013 7:03 AM (in response to Mickey Oksner)
run at the slower speed. "Cost" is small 4% hit.
8 DIMMs though offers 17% better memory bandwidth performance than using less DIMMs
Amazon has new highest quality 667s @ $33 2x2GB kit making them very affordable.
If you need 4GB DIMMs, that is when price jumps very high.