should I listen to bios or speedfan vcore?

[wstcoaster07]

Ok, so here is my issue.... in order to get my e6750 stable @3.6 I have to run the bios vcore to 1.525. Now, I know that is high, however, speedfan only reads it as 1.49 (dropping to 1.48 under load). Should I assume I am really just running 1.49 and feel fine sending my "vcore bios" settings high to account for the diff in numbers?

 

[itotallybelieveyou]

In Speedfan I trust

 

[Hatman]

BIOS setting is higher then what it actually runs, in my 680i lt even in BIOS I set it to 1.33 or something yet right next to it is says I'm set to 1.3v, speedfan shows 1.3v too. CPU-Z aswell.

 

[systemlord]

Thing is the senser that the bios uses is the same one Speed Fan uses. I thought I was having a problem with my PSU because my +3.3v, +5v rails were reading 31% lower that my DVM did. The reason measuring at the mobo 24 pin connector is better is because heat/resistance by the time it gets to the bios your reading are off.

 

[CompuTronix]

wstcoaster07, CPU-Z 1.41 wll display Vcore to 0.001 volts. SpeedFan 4.32 / 4.33 / Beta 4.34 will display Vcore to 0.01 volts on the default "Readings" tab, and 0.001 volts on the "Charts" tab, which is an extremely useful function for observing voltage and temperature trends over time. Both programs will display identical values.

There are 4 considerations regarding Vcore:

(1) Vcore Applied / Vcore BIOS: The difference between Vcore measured by the voltage regulator output compared to Vcore displayed in BIOS. Vcore BIOS is acquired as a digital value from the motherboard's super I/O chip, which performs (A)nalog to (D)igital conversions. The super I/O chip acquires the analog level from voltage divider circuits which monitor Vcore Applied to the CPU from the voltage regulator outputs. Analog accuracy is determined by voltage divider component tolerances, and Digital accuracy is determined by bit conversions between Vcore requested and Vcore applied.

(2) Vcore BIOS / Vcore Idle: The difference between Vcore displayed in BIOS compared to Vcore Idle displayed by Windows Utilities such as CPU-Z and SpeedFan. Vcore BIOS may differ from Vcore Idle displayed in Windows Utilities due to chipset drivers and software code.

(3) Vcore Idle / Vcore Load: The difference between Vcore Idle displayed by Windows Utilities and Vcore Load displayed by Windows Utilities. This describes the typical decrease in Vcore when the voltage regulator circuits are under a load condition compared to a no-load condition. As load increases, heat increases, resistance increases, and voltage decreases. This is frequently called "Vdroop", which is an incorrect term that caught on like a bad nick-name. The correct electrical engineering term is "Voltage Sag".

(4) A high quality Digiatal Volt Meter (DVM) remains the most accurate means of measuring Vcore.

Comp