If you have a Core2Duo CPU it has "speedstep" .
Speedstep makes the CPU run slower by reducing the CPU multiplier until the CPU is put under a heavy load then it "revs" up to full speed.
As an example , I have a 2.66GHZ CPU with a 10X multiplier.
In normal operation the multiplier would drop to 6X & the CPU would run at 1.6GHz until the CPU was put under a heavy load, then it went to full speed.
[I disabled speedstep in the BIOS, manually set the multilpier to 10X , & increased the FSB to 320, & run the CPU at 3.2 all the time.]
All of that affects the memory .
Your unit woyld have been a tad slower with 533MHz memory .
You can download PC Wizard & use the Bencmarking feature to compare different memory speeds.http://www.cpuid.com/download/pcw2008_v1871.exe
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