The memory is controlled via the mainboard northbridge.
The memory will provide a small increase in performance at stock speed however if you overclock the CPU the faster memory may allow you to run a higher FSB and get a better OC from your CPU
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Yes and as it's based on the 650i chipset you can set memory and CPU FSB speeds seperately.
Just make sure to set the DDR2 voltage correctly in the BIOS... high end memory is usually 2.1 - 2.3V vs 1.8V default. It needs the higher voltage to operate at full speed. The Dimm should be labeled with the correct voltage.
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