higher latency numbers do not equal slower ram. DDR3 1333 with a CAS latency of 8 is exactly the same speed as DDR2 667 with a CAS latency of 4. Latency is not the measure of time but rather how many cycles are completed. the DDR3 performs 8 clock cycles in 12ns where the DDR2 performs 4 clock cycles in 12ns. it actually takes the DDR3 1.5ns for one clock cycle compared to 3ns for the DDR2.
DDR3-1333 Speed and Latency Shootout | Tom's Hardware
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