Core i7 and memory multipliers?

TossedSalad

Junior Member
Jan 9, 2007
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Okay, I've been reading up on this and I wanna make sure I've got this right. Let's assume I have a core i7 920. The speed = 2660MHz, or 20(multiplier) x 133MHz(Bclock), correct? So if I have DDR3 1333MHz, it's going to underclock at 1066MHz, or 133MHz(Bclock) x 8(memory multiplier), right? Now I read somewhere that core i7 supports 6.0, 8.0, 10.0, and 12.0 memory multipliers. So if I change the memory multiplier to 10, the memory will run at a rated speed of 1333MHz, right??

Thanks.

EDIT: If I have the GIGABYTE GA-EX58-UD3R mobo should I have a problem with the 10.0 memory multiplier?
 

Blain

Lifer
Oct 9, 1999
23,643
3
81
The lower end 920 and 940 lock the memory multipliers to a max of 1066.
But OCing will allow for faster memory speed.
 

TossedSalad

Junior Member
Jan 9, 2007
17
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0
Originally posted by: Blain
The lower end 920 and 940 lock the memory multipliers to a max of 1066.
But OCing will allow for faster memory speed.

Okay so the only way to get the ram running at 1333MHz is to overclock the Bclock to 166 MHz? (8.0 x 166MHz = 1333MHz)
 

Yellowbeard

Golden Member
Sep 9, 2003
1,542
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Originally posted by: Blain
The lower end 920 and 940 lock the memory multipliers to a max of 1066.
But OCing will allow for faster memory speed.

Actually, this is incorrect. Intel decided late in the release to unlock the memory multipliers on the retail 920 and 940 CPUs. They both allow stock dividers up to 14 (aka 1866) on most of the top end MOBOs.
 

TossedSalad

Junior Member
Jan 9, 2007
17
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0
Originally posted by: Yellowbeard
Originally posted by: Blain
The lower end 920 and 940 lock the memory multipliers to a max of 1066.
But OCing will allow for faster memory speed.

Actually, this is incorrect. Intel decided late in the release to unlock the memory multipliers on the retail 920 and 940 CPUs. They both allow stock dividers up to 14 (aka 1866) on most of the top end MOBOs.

So is this only true in a later revision of the 920 and 940s?
 

Yellowbeard

Golden Member
Sep 9, 2003
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Yes, the retail 920/940 CPUs have unlocked memory multipliers. Oddly enough, the ESs are locked.
 

BonzaiDuck

Lifer
Jun 30, 2004
16,625
2,024
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Originally posted by: Yellowbeard
Yes, the retail 920/940 CPUs have unlocked memory multipliers. Oddly enough, the ESs are locked.

Keeping up with all this will not only cost me money -- it looks to be a P-I-T-A.
 

exar333

Diamond Member
Feb 7, 2004
8,518
8
91
You beat me to the link on this!

Yellowbeard is right, this change was not announced with much fanfare from Intel. It is really nice having these unlocked; I wonder if they will leave them unlocked only for the i7, or if they will follow-suit with the i5 as well.

Edit: SP
 

Yellowbeard

Golden Member
Sep 9, 2003
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It was a welcome change to memory makers and memory enthusiasts alike. We'd all have much fewer options if we were limited to only BClock changes. That would be no different really from the 775 Core 2 and previous days.
 

exar333

Diamond Member
Feb 7, 2004
8,518
8
91
Originally posted by: Yellowbeard
It was a welcome change to memory makers and memory enthusiasts alike. We'd all have much fewer options if we were limited to only BClock changes. That would be no different really from the 775 Core 2 and previous days.

Yes, I agree 100%. Once the 4GB DIMMs become more available, this ability will be even more useful. The only ones I have seen so far are very expensive and also at very slow speeds. The i7 has so much memory bandwidth anyway, that being able to slow the memory speed down asynchronously and have the maximum memory will be a breeze.

+1 for Intel on this decision. I feel as if they have been trying hard lately to appease the enthusiast crowd. They first enabled xfire and SLI on the X58 boards and then released the memory multipliers.