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Memory performance
Memory subsystems don't always dictate performance in real-world applications, but these synthetic tests are the most direct way to explore the impact of the P35's DDR3 memory controller.

With DDR2-800 memory, the P35 Express offers equivalent memory bandwidth and latency to its P965 predecessor. Working DDR3 into the mix yields more bandwidth in both Cachemem and Sandra, and with our DDR3-1066 sticks, latency improves, as well. However, our DDR3-1333 system's latency is quite high, no doubt thanks to its conservative 9-9-9-24 memory timings. There's nearly a 20 millisecond latency gap between the P35 Express with DDR3-1333 and the nForce 680i SLI with DDR2-800—a virtual eternity within the confines of a modern PC.

The following Cachemem latency graphs are a little indulgent, but they do a good job of highlighting access latency across various block and step sizes. The Core 2 Duo runs out of on-chip cache after a block size of 4096KB, so you'll want to pay more attention to the memory access latencies that follow with larger block sizes.

I've arranged the following graphs in order of highest to lowest latency with a common Z-axis to aid comparison.

Amusingly, the DDR2 memory controller in Intel's aging 975X Express chipset manages to offer much lower latency than the latest P35 Express. The P35 is really a replacement for the P965, though, and the two are evenly matched with DDR2 memory. DDR3 running at 1066MHz with 7-7-7-21 timings looks to be a reasonable option, as well, since it doesn't suffer the latency penalty associated with our DDR3-1333 config.

Still, the nForce 680i SLI's DDR2 memory controller delivers by far the lowest access latencies of the lot.