How much faster is this PC2 5300 memory versus this PC 3200?

[2048Megabytes]

How much faster is the data transfer rate of PC2 5300 memory versus this PC 3200 Random Access Memory if they are both running at their peak rates? What I am not understanding is how much CAS Latency slows memory down.

Kingston 2 gigabyte (2 x 1 gigabyte) 240-Pin ECC Unbuffered PC2 5300 (DDR2 667) Dual Channel Kit Server Memory, CAS Latency 5, 1.8 Volts


SUPER TALENT 2 gigabyte (2 x 1 gigabyte) 184-Pin PC 3200 (DDR 400) Dual Channel Kit Desktop Memory, CAS Latency 3, 2.5 Volts

 

[Geoff]

CL5 is very high for DDR2 667, to give you an idea i'm running my DDR2 930 at CL4.

Anyways, to find out I would download SiSoft Sandra, as they have memory bandwidth tests where you can compare different types of memory.

 

[Cromewell]

You can do the math your self if you want, it's not that hard. DDR2-667 isn't in there but I'm sure you can figure it out

Hertz - A measurement of frequency in cycles per second. One Hertz is one cycle per second.

With that in mind:
DDR-400 (or 200 MHz) completes 1 cycle in 5 nanoseconds.

To actually do the math:
1 second / 200,000,000 Hertz = 0.000000005 seconds / hertz (5 nanoseonds per cycle)

DDR2-800 (400 MHz) completes 1 cycle in 2.5ns.
DDR3-1333 (667MHz) completes 1 cycle in 1.5ns.

DDR-400 @ CAS2 the latency is 10ns.
DDR2-800 @ CAS4 the latency is still 10ns.
DDR3-1333 @ CAS9 is 13.5ns.
DDR3-1333 @ CAS7 is 10.5ns.

 

[2048Megabytes]

Making a little more sense now.