CAS latency calculation?

[cbjaust]

In your guide TTR's Guide to Determining Optimum Overclocked System Performance Points (http://www.thetechrepository.com/showthread.php?t=195)you state that the calculation for CAS latency is CAS x 2000 / Freq MEM (Data Rate MHz) .

My question is why do you use the DATA rate as the frequency in the calculation and then also use a constant of 2000 to make the calculation come out right?

Would it not be simpler to make it like this?: CAS latency (ns) = CAS / Freq MEM (Base Frequency in MHz) and then convert to your favourite units at the end?

eg DDR2-1000, CAS 4: CAS latency = 4 / 5x10^8 = 8x10^-9 s (x 1x10^9) = 8.0ns

Also, does this mean that CAS2 PC3200 has a CAS latency of 10ns ?

Thanks

PS your articles are very informative and any articles pertaining to how all of the timings and (A64) subtimings relate would be very welcome.