Memory Overclocking - DDR460 vs. Better Timings

[Strife21]

I have a question, I wanna know if I end up Overclocking a Opteron 170 to 2500mhz
10x250 for example. I have memory that can overclock to about 230mhz.

Would it be better to run the memory at:
227mhz (DDR454) 11:12 and at 3-3-3-8 timings
or to run the memory at 208mhz (DDR416) 5:6 at 2.5-3-3-6 timings?

I am using the system to play 3-D games.

 

[RichUK]

That extra bandwidth is negligible, go as far as you can on CAS2.5. This will yield better performance.

 

[spiritwalker2223]

Run it at DDR416, lower latencies give a lot better results than increased bandwidth on AMD's.

 

[Diasper]

Actually dual-core benefits from the extra bandwidth (hence the promised extra performance from M2 using DDR2 667mhz etc). There was an anandtech article not long ago on extra bandwidth for AMDs and AMD dual-core's - they do benefit in short but not by crazy amounts. I'm too lazy to find links now.

If you were single-core I'd probably still say go for the higher bandwidth option given the 0.5Cas difference (negligible really). While some sides say there's no improvement with extra bandwdith (eg Zebo) others have done tests (Anandtech with a FX chip) and received extra speed from the bandwidth. These tests were all probably done at 2-2-2 at different speeds - I can't quite remember.

I'd go for the higher bandwidth option consequently at 2.5-3-3 vs 3-3-3 is neglible really. Have you also tried 3-3-2 or 3-2-2 as they might yield better memory benchmarks. See how far those timings take you.

On a more general point have you tried to see how your RAM responds to extra voltages? I'd say try all the way upto 2.8V as you are probably running value RAM that probably risks not like / burn out with more voltages.

 

[Strife21]

do the higher voltages just enable me to get the fsb up higher for the memory?
or will that help enable me to lower timings more?

 

[Diasper]

Both actually. Say you increase your voltage and find your optimum (fsbs will find a maximum fsb/best timings at a certain voltage and then decrease/overheat after that)

Possible scenario you find your maximum voltage:
You might find you are able to push 2.5-3-3 at DDR450
You might find you are able to push 3-3-3 at DDR490
And you might find you are able to to do 2.5-2-2 at DDR400 when you couldn't at all before.

..Maybe anyway

But you get the idea - it can increase the fsb you can do certain timings at.