I have a P4 3.2ghz 800mhz FSB.
Would DC PC4200 DDR2 improve performance, and most importantly, why/and are there benchmarks?
Yes, because in single channel mode your memory<->CPU bandwidth is limited by the 533MHz data rate of the DDR2-533 RAM. Your CPU's FSB has a data rate of 800MHz. Dual-channel mode increases the memory bus data rate to 2x533MHz = 1066MHz, allowing it to saturate the 800MHz FSB data rate. Of course, there are synchronous/asynchronous and latency effects, and memory<->CPU throughput isn't the only limit on performance.
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