Overclocking RAM?

doakwolf

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Apr 26, 2009
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Hi all,

Should I be able to overclock my RAM past it's 'tested' clock speed?

OK - I'll elaborate. I have XMS3 Corsair 1600MHz RAM. I wondered if I should be able to run it @ say 1660MHz etc or is 1600MHz the absolute maximum it can handle?

Every time I try to crank it past 1600, my PC freezes or doesn't boot at all so I figure the answer is NO but wanted to check to see if there's anything else I can tweak to get it stable at 'slightly' higher than 1600?

Even just a tiny bit over 1600 (say 1610MHz) and it's completely unstable.

P.S. I have the voltage @ 1.64v and have also tried 1.66v (1.65v not possible with my MB).

Cheers,
Jero.

P.S. I'm really only interested because I've been wanting to change my i7 920 OC from 174BCLK x20 to 166BCLK x21 thus increasing my RAM speed from 1392MHz to 1660MHz. Not that 1392MHz is slow, and I realise there might not be a performance increase, but I'm just enjoying tweaking and learning about OCing.
 
I don't see why you would want to do that anyways.... 1600Mhz is stupid fast.....You can overclock that 920 without touching the Ram speed.....

I am using DDR2 800Mhz and it is fast enough for my needs ATM......
 

doakwolf

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Apr 26, 2009
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Hi there,

OK thanks to all for your advice. My confusion now is with some of the above comments about leaving the RAM speed at stock whilst OCing the 920.

I am very new to OCing.

I thought the RAM speed HAD to be a mutliplier of the BCLK?

So in order to OC my 920 to 3.48GHz, I can do it a few ways:

A) BCLK @ 174 (CPU multi @ x20) and RAM multi @ x8 (1392MHz)
B) BCLK @ 166 (CPU multi @ x21) and RAM multi @ x10 (1660MHz)
C) other BCLK vs multi combos

So how do I OC the 920 without changing my RAM speed, OvrClkr? I have Asus P6T Deluxe.

Cheers!

Jero.

P.S. If 1660MHz just isn't possible with my RAM, then sobeit! I'll live :D

I might try different timings as per above advice.
 
You set the ratio between your BCLK and memory speeds using the memory divider: i.e. Use a lower number. While playing with the processor Overclock, you should set the memory divider so you don't exceed the rated speed of your RAM. The reason why is you absolutely *will* run out of headroom on your memory far far far sooner than you would with a processor overclock.

If that was a little confusing: For example, you might possibly be able to get 5% on your memory modules. But you should easily get 30%+ on the processor. Now, if the two are both at their rated speeds and you begin overclocking you absolutely will run into memory problems almost straight away. Because the memory won't overclock any more, your processor is also limited.

SO - Instead, you will set the memory divider to run your RAM well below it's rating - Say, 800 MHZ. Now you have lots and lots of headroom on the memory side. Headroom which you can use to get your processor running at speed. And because you have all of this room to play with, if you run into a problem now you can be reasonably confident it's related to the CPU and not the RAM. So doing it this way cuts your troubleshooting possibilities in half, as well.

After you have completed a nice, long (12~24 hour) stress test and are assured your processor overclock is solid. *Then* you can go back and play with memory at your convenience.


I will reiterate my earlier caution: It's my experience - both personally and from participating in the boards here - that Memory is by far the #1 source of instability in a new build. And it's been proven (please read the article I linked above) that faster memory provides little to no gain in real performance. You can try if you must, but I'll repeat my recommendation you forget the idea of overclocking your RAM.
 

bpogdowz

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Actually it's the motherboard that gets fubared. Experience: bricking two mainboards with 1.9V RAM. Fries up in 2 seconds.