i7 960 question

coachingjoy

Junior Member
Jul 19, 2009
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This might be a silly question but I don't know the answer.

As the title states; I bought a 960 cpu and it's rated at 3.2G [24 X 133].

To check my setup I ran Prime95 for a short run for heat testing.

My CPU is running at 25 X 133 with 8 threads fully loaded = 3.33G.

Increases in multiplier were for single threaded apps...At least that is what I thought.

Is this, in fact, what is taking place here?

TIA for any info.
 

ekoostik

Senior member
Sep 10, 2009
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I couldn't find anything specifically about the 960. But take a look at the Lynnfield article and the table breaking down Turbo mode speeds based on active cores: http://www.anandtech.com/cpuchipsets/showdoc.aspx?i=3634&p=5

You'll notice that even with 4 cores active the chips are capable of running at +1 multiplier (or +2 in the case of the i7 870). So what you're seeing doesn't surprise me, even though this is comparing Lynnfield to Bloomfield. But hopefully someone else will come up with something more concrete.
 

ekoostik

Senior member
Sep 10, 2009
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That's a good article, with the relevant information being:
... but with Nehalem's Turbo mode all four cores can overclock themselves if temperatures are cool enough. Each Nehalem can run its four cores at up to 133MHz higher than the stock frequency (e.g. 3.33GHz in the case of the 3.2GHz 965 model), or if only one core is active then it can run at up to 266MHz higher than stock (3.46GHz up from 3.2GHz).

So what it's saying is that every core in a Bloomfield chip is set to run at a certain spped - for the i7 965 this is 3.2GHz. However, any given core at any given time can up it's multiplier by 1 IF temperatures are not too hot. As an added bonus, when only one core is active that core's multiplier is raised by 2. In this case it must still be true that temperatures are not too hot, but power is cut to the other cores which helps ensure that the one active core can be boosted.

Per the article I linked to previously: Lynnfield is similar because it can increase the multiplier by 1 (and the i7 870 can increase it by 2) even if all 4 cores are active - once again IF temperatures are not too hot. But Lynnfield has a more flexible Turbo because it can increase the multiplier even further for each inactive core, unlike Bloomfield which only gets another 'turbo' boost when 3 cores are inactive, i.e. if 1 core is active.