Which Voltage Reading do I trust?

Light1984

Gawd
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Dec 31, 2004
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588
I am trying to overclock my phenom, and it is not stable with voltage set to auto. So I decided I would bump the voltage a little, currently, I have 1.3v set in the bios (v 0502) and it reads 1.28v in both everest and cpuz. I had it set to 1.28v in bios before, and it read 1.26 in everest and cpuz. So it is off once I am in windows by .02v. I guess that really isnt that much to worry about, but which one do you guys think is accurate. Currently, I am at 2990 Mhz :rolleyes:
 

Nosenuggets45

Limp Gawd
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Jun 6, 2008
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I believe that is because of the Vdrop, so I'd go with your mobo voltage. I'm not 100% certain so hopefully someone else can clarify what I've said.
 

evilcartman

[H]ard|Gawd
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Sounds like Vdroop to me. I agree with the poster above me, I'd trust the voltage set in your BIOS over a software reading.
 

necrophile

[H]ard|Gawd
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Sep 6, 2008
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Pretty sure you go with cpu-z here. What you set in the bios is your expected voltage but what you are actually using is reported in cpu-z if i am not mistaken.

I believe you can set your mobo to adjust it using the load line calibration setting, not sure, bit of a newb at this.
 

Elios

Supreme [H]ardness
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Aug 12, 2004
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you would be suprised at how many mobos under volt from what you set in the first place

the VID that you set in bios isnt always the real vcore you get
 

Riccochet

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I would go with what CPUz/Everest is reporting. As others have stated you'll get vdroop, so what you set in BIOS is not what the CPU is actually getting. .02v at idle is nothing to be concerned about. See what the difference is at load, you'll be surprized. I lose almost .1v at load from what I have set in BIOS and about .05v at idle.
 

merc68

Limp Gawd
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Dec 29, 2004
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It is fairly common not to get the full voltage you set in bios. My board is set to 1.2125v and I'm only getting 1.184v
 

Slade

2[H]4U
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Jun 9, 2004
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Trust the voltage setting that is the lowest possible value while keeping prime stable for > 8hrs.
 

Zero82z

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It is fairly common not to get the full voltage you set in bios. My board is set to 1.2125v and I'm only getting 1.184v

Due to Vdroop, your voltage while idle is usually a bit lower than what you have set in the BIOS. It's done this way to ensure that voltage spikes caused when the CPU is loaded don't reach levels high enough that could damage the chip.
 

sirmonkey1985

[H]ard|DCer of the Month - July 2010
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Sounds like Vdroop to me. I agree with the poster above me, I'd trust the voltage set in your BIOS over a software reading.


your answer just proved why he should trust the software.. the bios doesnt show vdroop in the overclock settings.. only way to see the vdroop is looking in the heath monitoring section of his bios.. it will show the actual voltage there.. and its the same voltage cpu-z will read as well..


and OP do not ever trust auto settings on voltages when overclocking.. each motherboard acts differently.. some will over-volt and some will under-volt what the actual voltage needs to be for the overclock to be stable..
 

Blazestorm

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Jan 17, 2007
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I set mine to 1.275 for the Q6600 @ 3.0ghz (Lowest VID I got)

And when it's under full load it drops to 1.2 ... but still stable... IP35 Pro has terrible v-droopz.
 
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