Confused about CPU VID

[Buuntu]

So I've read on several sites that the VID of a processor is the amount of voltage used on stock settings. If that is the case, why are there different values for the VID between people that have the same processor? Like the i5-2500k for example, CPU-Z shows my VID to be 1.3661v but I've found people claiming that their VID is different (like 1.0057v). Can someone clear this up for me?

 

[Cygnus x-1]

Because not all processor are the same even the ones that are the same series or model. They are tested and VID stamped sort o speak before going to box. Similar process that is used if not the same for the cpu binning process.

 

[Buuntu]

But then why does my VID change in CPU-Z? Like it used to be 1.3666v (I think) and now it's 1.3861v after overclocking to 4.5 GHz. Also if that is how it worked it seems like the difference would be much smaller than it actually ends up being.

 

[Cygnus x-1]

Are you overclocking with turbo on? If so the mobo will add extra voltage to handle the higher frequency when you load the cpu with turbo enabled. One of the reason's I like overclocking with turbo enabled by the way.

 

[jsc]

The VID will not change. The VID is the voltage that the CPU programs the motherboard CPU power regulator to produce. This is based on certain CPU pin assignments and is set during manufacturing and testing. This will vary from chip to chip within a specific range. The VID range (based on Intel docs) for a Q9550 is .85 - 1.3625 volts. Most seem to fall around 1.25 volts. Lower is obviously better.

The motherboard/CPU can change the core voltage depending on speed and load factors. The CPU voltage that CPU-Z reports is the core voltage, the voltage applied to the CPU. That is not the same as the VID.

 

[Buuntu]

Sorry, I meant to say the VID on Core Temp. For example, right now Core Temp says that the VID for my i5-2500k at 4.5 GHz is 1.3861v. Maybe it's just core temp though, because that seems ridiculously high to be the VID and it certainly isn't the Vcore since that's set to 1.33v.

 

[Cygnus x-1]

Like Jsc said the vid won't change, the voltage can and will depending on load.

 

[Buuntu]

Yeah that's what I originally thought, so is Core Temp just wrong?

 

[Cygnus x-1]

Are you sure your not confusing VID with voltage?

 

[Buuntu]

Yes...

http://img.techpowerup.org/110809/Capture006274.jpg

Where it says VID, that number sometimes jumps down to 1.3861, depending on the load I think.

 

[jsc]

VID is fixed. That is a difference of .005 volts. What I think you are seeing is a single bit (LSB) error in the output of the A/D conversion. Don't worry about it.

 

[Buuntu]

It's a difference of *.05v. But isn't that still absurdly high for an i5-2500k? I think most people have it close to 1.3v if not a little lower.

 

[Danny111]

The VID will not change. The VID is the voltage that the CPU programs the motherboard CPU power regulator to produce. This is based on certain CPU pin assignments and is set during manufacturing and testing. This will vary from chip to chip within a specific range. The VID range (based on Intel docs) for a Q9550 is .85 - 1.3625 volts. Most seem to fall around 1.25 volts. Lower is obviously better.

The motherboard/CPU can change the core voltage depending on speed and load factors. The CPU voltage that CPU-Z reports is the core voltage, the voltage applied to the CPU. That is not the same as the VID.

Okay that is extremely odd. Because on my CPUID HWMonitor, under ASRock Z87 Extreme 4 -> Voltages -> CPU VCORE is 0.944V min and 0.952 max and barely changes.

But under Intel Core i5 4670K -> Voltages -> VID I have 0.709V min to 1.199 max (with 1.267 max when I run Intel Burn Test or Prime95) (I run "adaptive" rather than "override", if I use the latter it is always on what I input into override voltage).

Because reading your explanation, the labels are exactly swapped. The one labelled VCORE is the one not changing but the one labelled VID does change.

N.B. CPU-Z has under the label Core Voltage the exact same that CPUID HWMonitor has VID (they don't agree 100% e.g. one might be a split second faster to change, but overall it's the "same"). While Core Temp under VID has 0.825.

So is this an error on the HWMonitor version I have that it has the wrong labels?