I am putting together a low cost AM3 Sempron 140, based on the Sargas/Regor core, system. The on chip mem controller supports DDR2-800 or DDR3-1066. I have this paired with a Biostar MCP6P M2+ motherboard that uses the nforce430/6150 chipset and supports up to DDR2-1066 with a AM2+ CPU. My question is, with the CPU mem controller only supporting up to DDR2-800 will I see any benefit of getting DDR2-1066? My memory options are between a Crucial 2GB DDR2-1066 DC kit or a Crucial 4GB DDR2-800 DC kit, the later being only $10 more.
Memory speed won't really give you any extra performance with such a slow system. A higher-end CPU would see a benefit, but with this system, the CPU is the bottleneck.
