Which memory speed/timings would be faster?

[Staz]

On an overclocked system, would I get more speed from memory running at 221MHz at 3-3-3-8 timings or the same memory at 177MHZ at 2-2-2-5 timings? Or would I even notice the difference?

 

[theMan]

you probably wouldnt notice the difference, unless you benchmarked. it would depend on which apps you are running.

 

[wildcat86]

I think MHz matters more than timings, especially when the diffrence is almost 50MHz here

I remember hearing that different timings didnt really change performance all that much with an A64

 

[Matt2]

Bandwidth vs Timings

In the above thread I found that high bandwidth/loose timings yield the same performance as low bandwidth/tight timings.

The best performance I found was a balance between bandwidth and timings. There certainly is a "sweet spot" when it comes to memory settings on A64.

 

[Hacp]

The first one is better. 221 at 3-3-3-8 will beat 177 at 2-2-2-5
http://www.xbitlabs.com/articles/cpu/display/athlon64-e3-mem_8.html

Compare ddr 480 to DDR400. Difference is 40 MHZ, about what your difference is. Timings are similar to yours. I know its cas 2 for the 480 one, but you have to take diminishing returns into account.

 

[wildcat86]

i didnt even factor in that your probably limiting your CPU by running at lower than 400MHz DDR

 

[Mucker]

Scroll down for some good bar graphs: http://www.xbitlabs.com/articles/memory/display/ocz-ddr600_4.html

If you can run your memory DDR600, there will be a gain, but really nothing to write home about. In your situation, the fsb difference is not enough where you will notice anything at all. Run your CPU at the highest safe frequency with tight timings. That is best for A64.

m

 

[Hacp]

Mucker did you look at the charts I posted??????????? I would avoid runinng 177 MHZ.

 

[Mucker]

Originally posted by: Hacp
Mucker did you look at the charts I posted??????????? I would avoid runinng 177 MHZ.

I sure did, I don't see any 3-3-3-8 numbers in those charts. There is quite a difference in CAS 2 and 3.

The OP is talking about a 44MHz difference between 2-2-2-5 and 3-3-3-8. I'd like to see his benchmarks on both. My bet is that they are about equal.

m

 

[Hacp]

You have to take into account that a 30 MHZ increase from 170 to 200 is going to be more effective than going from 200-230.

 

[Mucker]

Like I said, only a benchmark would show us....it's all speculation otherwise...

m

 

[Hacp]

Either way performance difference isn't noticable nyways.

 

[spiritwalker2223]

you guys need to run some numbers, and remember some rules.

1. latency is no. 1 for AMD systems, Period.
2. Same latency but higher bandwidth returns small performance increase(again for AMD).

Stax, from this and the numbers you posted at the beginning your best bet is to use the ram at 177 2-2-2-5. It will give you a cas latency of 5.65ns, while using the @ 222mhz gives you a cas latency of 6.8ns.