Will higher spped RAM help with overclocking?

[drakos]

I am considering picking up a 6GB kit of Dominator 1866 memory. The price is considerable more than the 1333 and 1600 versions. Is this a worthwhile upgrade and will I have a higher chance of a sucessful overclock with higher speed memory?

[randomness]

Re: Will higher spped RAM help with overclocking?

Of course, When your OC'ing, you can set the mem multiplier to the minimum then as the fsb or w/e increases, memory will still have headroom before it reaches its limits.

[Nickel020]

Re: Will higher spped RAM help with overclocking?

He has a Core i7, so no FSB there. Whole different story.

I haven't OC'ed Core i7 yet, but afaik know memory is not a limiting factor there, rather the opposite: it's hard to get RAM working at close to an effective 2000 MHz (if you got RAM that can do that that of course).

Take a look at this list, people are running memory rather slow here and achieving high overclocks. If you can do 4.2GHz at DDR3 ~1200 I guess you could say memory speed won't be limiting you.
[Sammelthread] Intel Core i7 - Nehalem-Bloomfield OverClocking Thread (2) - Forum de Luxx

[drakos]

Re: Will higher spped RAM help with overclocking?

So is it wasteful for me to go with the 1866 ram?

[Lsdmeasap]

Re: Will higher spped RAM help with overclocking?

If you have a 920/940 then yes, your limit on the ram speed will be in the 1600-1700 range.

If you have a 965, then any will be fine

[drakos]

Re: Will higher spped RAM help with overclocking?

So I should go with the 1600 ram vs 1866? Wouldn't the 1866 provide more of a buffer and more stability? If I run the 1866 ram at a lower frequency, would I be able to set tighter timings?

[Nickel020]

Re: Will higher spped RAM help with overclocking?

Did you look at my link? There are people running thei Core i7 at 4.1+Ghz with a RAM speed of just 600MHz or only slightly more.
If you think higher speed RAM will get you more performance, then by all means get it. But it will not help you achieve a higher overclock.

[drakos]

Re: Will higher spped RAM help with overclocking?

The cost difference is a $100CAD for 1866 vs 1600. If it is not worth it then I will go with the 1600.

[Nickel020]

Re: Will higher spped RAM help with overclocking?

Spend that on better video card and youll see much more of a performance increase.

Tests have actually shown that there's little difference between running Core i7 in triple or dual channel mode. So if cutting 1/3 of the bandwidth doesn't have much of an effect then a 166MHz more will probably not be noticeable at all.

[drakos]

Re: Will higher spped RAM help with overclocking?

I will listen to your wise advise Nickel, thanks for that. Now has anyone actually tried and used XMP mode in the bios? Doesn't XMP automatically set up voltages, timings so RAM and CPU run at a 1:1 ratio? If so, why would you need to overclock? Sorry for being such a noob.

[Lsdmeasap]

Re: Will higher spped RAM help with overclocking?

The i7 920/940 are limited by the ram multi (6 or 8) x bclk so the highest you can run your ram is 1600-1700, with 1600 having your CPU at close to if not The max of 200 Bclk. Some wont even do 200, some will do 220+ but not much more then that.

It will in no way help with your overclock. And spending more $$ for something you cannot run at stock with the idea of underclocking it is a waste of money really. Get some 1600 and call it a day I would say

Yes XMP works if your ram is XMP Programmed, and it sets the ram timings, and ram voltage, and QPI/VTT voltage as well. Again that is ONLY if it is XMP programmed though. XMP only sets the above mentioned things, and you may only have one XMP Profile depending on the ram you buy. One may be 1333/667 and one may be 1600/800.

I have a set of Crucial's new Blue Tracers, here is what the XMP looks like in those so you can see what I mean (These have 2 1600/800 profiles in them, as well as 3 JEDEC profiles) >>>



As you can see in this BIOS image, the XMP set the Ram and QPI/VTT voltage per the XMP profile (Not all X58 boards may have this (The QPI/VTT XMP Part), I am not sure, but I would assume it is likely that they do) >>>



Do keep in mind EPP and XMP are not the same thing, so a EPP Programmed set may not work with XMP and for sure likely would not set voltages correctly

There is no 1:1 anymore, as there is no FSB in i7. You will be using 6 or 8 as a multi with a 920/940 CPU, those are your only choices

[drakos]

Re: Will higher spped RAM help with overclocking?

So if I enable XMP, I will still need to adjust the CPU settings? Like voltage, bclk etc..?

[Lsdmeasap]

Re: Will higher spped RAM help with overclocking?

Yes, you will need to set many things likely. Auto is never best for sure, on most all settings. And that goes for using XMP as well, it will not provide the best either only what the memory manufacturer has tested to be good and stable