Vdroop + Vcore Question

iantosca

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Aug 18, 2009
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It seems I have run into a little problem. My prior setup was:
Core i7 920 @ 3.5ghz, 1.21vcore, 1.18v under prime load, ddr3 1333mhz valueram at 1.5v

Now I have
Core i7 920 @ 3.8ghz 1.31 vcore, 1.25v under prime load, ddr3 1600mhz Corsair Dominator at 1.64v

I had to increase the vcore a HUGE amount with the new RAM to get a stable OC. Anything under this and I get BSOD memory dumps.

Why is there such a huge difference in required volts to my CPU now and on top of that ... why am I setting the vcore at 1.31 and getting 1.25 in cpuz under load? Isn't that a large vdroop? Before it was only 0.03v and now it's 0.06v.

If you have any advice please let me know.
 

drums101

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well cpuz might not be 100 percent accurate but there is always going to be vdroop under load unless your motherboard has a feature probably named something similar to load line calibration this will help stop vdroop....As far as the amount of vcore you needed well you upped the cpu speed so you had to increase the volts......it seems kinda high to me i have the 950 at 4ghz at 1.23v and its rock stable it could just be you dont have a good ocing chip...the ram didnt have an impact on the amount of vcore needed
 

iantosca

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Aug 18, 2009
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I would have thought the same thing but I had my chip at 3.5ghz rock solid on 1.21v and I don't even think I needed that when I had the 1333mhz loaded. I don't see how that would be my end point. I am even having trouble getting it stable at 3.5ghz now with the new memory in total. Otherwise I would agree.
 

darkling

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Feb 24, 2010
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The new memory needs more QPI\Vtt may have it listed as IMC in your bios. Probably 1.19 or 1.21. Qpi and vcore tend to work together so i am guessing your qpi\vtt is 1.1 and that is requiring more vcore. Raise the qpi\vtt and lower the vcore. As a matter of fact let the Cpu Vcore on Normal and see what your CPU VID is and you can fine tune using Dynamic Vcore (DVID)