At 4.0GHz, still 1.66 VDIM??

t33lo

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I have an i7 build (check signature) and have it sucessfully overclocked and stable at 4.0GHz. I remember back in the day you had to bump up the VDIMM in order to keep stability. With such a high overclock, how come I don't even have to touch either the TIMINGS or the VDIMM? I am running at 1.36V on my D0 and 1.66 on VDIMM @ 7-7-7-24 stock timings. Any ideas?
 

t33lo

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Not sure why all my posts disappeared and says im a "newbie" and my signature isn't showing up, so heres my system:

Intel i7 920 D0 Rev. @ 4.0GHz|Gigabyte UD4P|EVGA GTX 275 FTW @ 738/1570/1270|OCZ Platinum 3x2GB @ 7-7-7-24|WD Caviar Black 640GB|Seagate 320GB|Antec 1200|Zalman CNPS9900LED|Corsair HX-620W Modular PSU
 

t33lo

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thx for the reply, i actually didn't know that so it makes sense now. Another thing is that I hear the maximum throughput for the QPI is 6.2GT, but mine is set at 7.2 and I can't have it lower because it is 200BLC x 36. Is this ok?
 

t33lo

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Yeah I did up the voltage I think to 1.45 or 1.5. I get what you mean with your comparison, its just that the lowest you can go is x36, wheras the processor can drop down from 1x to 20x in succession.
 

paranoidmage

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And you joined in 1970, before this forum existed.
 

t33lo

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LOL i didn't even notice that, WTH did they do with the update?
 

jonnyboyC

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I wouldnt' see why you would i've have my i7 at 3.6 ghz. The ram doesn't have to be adjusted at all if your keeping at it's rated speed. I'm assuming your doing a 200 by 20 mulitplier and a 8:2 on the ram. As long as your memory is at speed it doesn't matter how it gets there a qpi 160 and a 10:2 ram which comes to 1600 again would act just the same as a 200 8:2
 

Helloworld_98

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you need to lower the vdimm to 1.64v, otherwise it will damage your CPU.

since with nehalem the max vdimm is 1.65 and ASUS P6T's don't support 1.65v so 1.64v is the max safe voltage.
 

t33lo

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an extra 0.02V would cause damage?
 
Gaming:
You should use the Task Manager (CTRL-ALT-DEL) to see if your CPU is reaching 100% during games. If NOT you are drastically increasing the in-game and idle power consumption with no benefit.

Leave the Task Manager running and play a few of your most demanding games. With one core it used to be easier to determine if the CPU was maxed out. With multi-cores and multi-threads it's not as easy. If no core/thread reaches 100% then you should throttle back your CPU.

Your CPU not being maxed out when gaming means your graphics card(s) is limiting things or you don't need any more power from your graphics or CPU (say running at 60FPS at max settings).

Again, many people overclock unnecessarily which can create stability issues, wear out your CPU and adds heat and noise. Don't overclock unless your at least one of your cores is maxed out at 100%.

I don't recommend clocking above 3.2GHz in general.