vDrop: trust the BIOS or Windows?

fepple

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Nov 5, 2007
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Hello!

I have a Asus P5K-E with a Q6600.

In the BIOS I set the vCore but then when I view it in CPU-Z/SpeedFan it displays differently. Normal enough vDrop. The difference in the reading is:

BIOS: 1.425v
Idle: 1.31v
Load: 1.30v

So my question is, do I trust the BIOS readings or the ones in Windows?

Cheers!
 

bildo123

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Feb 6, 2007
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I was told the reading from the lastest version of CPU-Z is the real-time voltage going to the cpu. So trust the one in windows. Seems as though your Vdrop is pretty big though at .115V's.
 

cnumartyr

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First, what BIOS version? 0906, 0602, 0603, 0706?

Long story short.. BIOS setting is VID. Then it Offsets it to actual idle voltage (read by CPU-Z). This is vDrop.

vDroop is Idle -> Load.
 

fepple

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Indeed I was worried about the vDrop, I was just reporting the Load and Idle voltages for completeness sake.

The voltages I reported are for 0906 BIOS, though I got a similar vDrop on 0502 and 0602. I was supprised to see it on 0602 as well because most reports I've seen suggested it wasnt present.

If I set the voltage to 1.425v then reboot and go back to the BIOS and look in the Hardware Monitor it will report the voltage as 1.30v (ish, I'm at work atm).

So I am going to distrust the BIOS setting and instead believe the BIOS reading/CPU-Z/SpeedFan.

Also, the BIOS Hardware Monitor version of the vCore more closely matchs the stability I would expect when pushing the clock speed to 3.6Ghz.


Thanks!
 

fbm211

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Thats a kickass rig you got cnumartyr...If you dont mind me asking how would I oc my shader clock. ntune only does core/memory.I have the evga8800gts(g92)