Memory - Choosing berween lower Latency and Clock Speed

[fendog]

I see there are 2 different sets of 6GB Corsair Dominator GTs both priced exactly the same (scan).

One is 1600MHz with CAS latency of 7-7-7-20, the other is 2000MHz with CAS latency of 8-9-8-24.

Since they are both priced exactly the same, how do you choose between them - If I'm gaming and overclocking is it more preferable to have a lower latency or a faster clock speed? If there is no noticeable difference then why have Corsair released 2 different sets?

(I'm not saying i'm looking to buy these I'm just curious to know how you would make the choice in theory)

Cheers:up:

[sn0man]

No noticeable difference between either other than synthetic benchmarks.

For an Intel system, I'd rather have the extra frequency rather than tighter timings - although you'll need more vtt/QPI voltage to maintain it.

[ripken204]

throughout the last few years it has been found that higher mhz is better than lower latency for most things you will do

[zanzabar]

i would bet that it wont make any diffrence and if the kits are not old stock anything that u get thats 1600mhz cas7 or or better will almost always be psc and the same chips as micron and elpedia dont make anything that clocks well (or atleast they are not common on the market and i have not heard of anything ATM)

[Carfax]

Memory speed is highly overrated, especially for the Core i7 which was designed to use up to DDR3-1333.

Generally speaking though, for the best performance, try to get as high a clockspeed as you can get, while maintaining as low a latency as possible.

That said, from the benchmarks I've seen (http://www.anandtech.com/show/2792/12), DDR3-1600 CL6 is about equal to DDR3-2000 CL8.

[fendog]

That said, from the benchmarks I've seen (http://www.anandtech.com/show/2792/12), DDR3-1600 CL6 is about equal to DDR3-2000 CL8.

That would explain the same price for each set, but wouldn't the 2000MHz give you more flexibility when using a serious CPU like a 980x?

[Carfax]

That would explain the same price for each set, but wouldn't the 2000MHz give you more flexibility when using a serious CPU like a 980x?

For overclocking you mean? Not as much as you think, since you can simply change the memory multiplier..

I can run my memory at 2ghz (even though it's rated at 1600), but I choose not to because I'd have to raise my QPI voltage substantially for a nonexistent performance increase.

[fendog]

For overclocking you mean? Not as much as you think, since you can simply change the memory multiplier..

I can run my memory at 2ghz (even though it's rated at 1600), but I choose not to because I'd have to raise my QPI voltage substantially for a nonexistent performance increase.

Yeah flexibility for overclocking.

Thanks all for the input, cheers.

[zanzabar]

That would explain the same price for each set, but wouldn't the 2000MHz give you more flexibility when using a serious CPU like a 980x?

that is missing the point of the 980x, unlocked chips u dont need high frequency since u are never base clock limited, you are always total clock limited as u have an unlocked multi. also all modern ram should give u much higher clocks with cas9 than 7 so its not like back in the ddr2 days were u had clock limited promos

[CrazyNutz]

One thing to consider, higher frequency = more power consumption, and more heat, where lowering the timings will not increase power consumption or heat.

I find I tend to lean towards tight timings, or atlest a balance.

[Hondacity]

One thing to consider, higher frequency = more power consumption, and more heat, where lowering the timings will not increase power consumption or heat.

I find I tend to lean towards tight timings, or atlest a balance.

1w more?

if you're dealing with large data....higher bandwidth helps..

if you're just doing internet...you don't need the extra bandwidth...

[Carfax]

One thing the OP might want to consider is running lower frequency and tighter timings in combination with a bump in the uncore as uncore has a significant effect on performance; probably more than frequency..

I just set my memory back to 1600 6-7-6-16 CR1, and I increased the uncore from the default 3800 to 4000. So far, this is giving me the best performance, even better than 2000 8-9-8-20 CR1 uncore set to 4000.

Of course, you'll have to increase your QPI VTT.

Another thing, lower your tRFC. The tRFC seems to be ridiculously high on the Core i7 platform for some reason. My default tRFC @ 2000 was 110, but I could drop down to 60 with no problems. At 1600, the default is 88, but I can easily run at 50.