Real vCore voltages?

[cythx]

When I set my vCore to 1.3750 V in the Bios, it displays it lower in CPU Z, and jumps down to 1.296 V when running Prime95

When I set my vCore to 1.3875 V in the Bios, it displays it lower in CPU Z, and jumps down to 1.312 V when running Prime 95

The same happens when I set my vCore to 1.4 V in the Bios, it displays it lower in CPU Z, and jumps down to 1.328 V when running Prime 95.

Which is the real one? Which one should I be looking at when comparing to others' posted voltages? I see other people posting lower voltages then my D0 i7 920 while keeping stable, while mine isn't. Is this because I'm comparing their CPU Z result to my BIOS setting? Thanks

Also, recently I've needed higher volts to keep stability, why is this?

Thank you

 

[saaiello]

OK your problem is called Vdroop read this article it will explain it really good and a quick tip if you enable load line calibration it will help it but read this article.

http://www.anandtech.com/cpuchipsets/intel/showdoc.aspx?i=3184&p=5

 

[cythx]

I'm going out in 2 minutes so I don't have time to read that but I'll ask this question.

Vdroop, should I turn it on or off? (or does it have various settings like voltages?)

Thank you very much, brb

 

[saaiello]

It has different settings depending on your board so do some research by google and read that article it will explain what it is the best then google about your settings in your bios.

 

[cythx]

Cythx wrote :

I need almost another .2 volts to get a stable 4 Ghz on my EX58A-UD3R Gigabyte board ;( sigh, glad my temps are the same though

Shadow70379:

Yeah man, the UD3R (both versions) have a massive vdroop (I couldn't get to 4Ghz at all even with quite a bit more than usual levels). Hence why I switched to a P6T Deluxe v2.

I must of missed this reply before but it looks like I have a massive vdroop.

Is it dangerous to test with vdroop or can I do some trial and error?

I'm going to read that article now

 

[saaiello]

You can mess with it a little but be careful with your settings and whatch your temps.

 

[JackNaylorPE]

You can set the BIOS to try and compensate for vDroop but that's been known to fry a board or two .....

http://www.anandtech.com/cpuchipsets/intel/showdoc.aspx?i=3184&p=5

 

[cythx]

Since the vDroop is much bigger on my board then other boards, doesn't that give me more leeway in reducing the vDroop?

Also my board gives me multiple levels of vDroop, it seems that the higher the level, the less of a vDroop I get.

So hopefully I should be safe with the lowest level vDroop (I lose .16 v to my CPU when torture testing)