Latency vs Command Rate

[Fuelrod]

What memory timings would be better from an overclocking and performance perspective:

A memory setting of 8-8-8-24 and 2T or 9-9-9-24 and 1T

 

[Spikesoldier]

IMO 1T or bust.

I base this opinion off of the old A64 OCing days.

 

[(sic)Klown12]

How about trying each and then deciding which works best for your situation. As far as I know, there is cut and dry answer to this as some applications will prefer the lower command rate while others the lower latency.

 

[EarthwormJim]

Here's a comparison for DDR3.

http://www.anandtech.com/show/2381/8

Look at the DDR1860 settings. You can see even with higher timings (CAS 8), a command rate of 1 is better than a command rate of 2 with tighter timings (CAS 7). That command rate of 1 at that speed performs even better than a command rate of 2 and higher clock speeds.

It logically makes sense that command rate has a greater influence on performance. You halve the latency when you go from a command rate of 2 to 1, while other timings you have a ~10% decrease. Command rate is important in most transactions too; it is the time between when memory is selected and when commands can be sent.