P8P67 : Explain CPU voltage offset ?

Anyone give a good example of how max CPU voltage can be predicted ?

It's seems related to offset , load line cal, and a base voltage.
Setting those to auto with a 45x mult shows 1.38 peak in CPUz under light load.

I'd like to put in specific settings and try to reduce the peak voltage used but still allow for the system to reduce voltage as needed.

Offset adds (or subtracts) a set voltage from what would otherwise be sent to the CPU under Auto. So if you set your offset at +.02, and the Auto voltage was going to be 1.35, it would instead send 1.37, and if Auto was going to set 0.95 it would instead 0.97. The benefit is that the board can still downvolt at idle, where setting a manual voltage (like 1.37) will send that voltage all the time, even when idle.

There doesn't seem to be any way of knowing what voltage you are going to get for a given speed ahead of time - so if you know you need 1.4 to run at 4.8, you'd have to try an offset, see what it gave you, and then adjust as necessary to get what you want. LLC is a player there as well, so you'd have to set that first, and then do the offset.

I fooled with it, then just gave up and set Auto, it sends more voltage than is probably necessary for the given overclock, but it isn't excessive and it is very stable (and it downvolts correctly).

If I set my 2600K to a 47 multiplier and Auto offset it sets the voltage at 1.496-1.504 which is obviously way too high. Actually any multiplier with an auto offset setting has the voltage way high. I'm still trying to figure out how to fix this.

Fighter2a said:

If I set my 2600K to a 47 multiplier and Auto offset it sets the voltage at 1.496-1.504 which is obviously way too high. Actually any multiplier with an auto offset setting has the voltage way high. I'm still trying to figure out how to fix this.

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I have mine set on Auto and it is pushing 1.33ish for 4.6 - not sure why yours would be so high for 4.7. Have you tried offset mode using a manual offset?

Fighter2a said:

If I set my 2600K to a 47 multiplier and Auto offset it sets the voltage at 1.496-1.504 which is obviously way too high. Actually any multiplier with an auto offset setting has the voltage way high. I'm still trying to figure out how to fix this.

Click to expand...

My tests have shown that offset = auto is not the same as offset = 0 (which is not an option). Indeed, after experimenting with it, I've found that offset = auto is about the same as offset = +0.030 with a 43x multiplier on my CPU, both of which yield an idle voltage of around 1.33.

offset with + .050 would give u around 1.4v

im running offset with - .015 and usually it stays at 1.232 load, but it does jump upwards to 1.28

LLC on regular

just got to experiment

Arkainium said:

My tests have shown that offset = auto is not the same as offset = 0 (which is not an option). Indeed, after experimenting with it, I've found that offset = auto is about the same as offset = +0.030 with a 43x multiplier on my CPU, both of which yield an idle voltage of around 1.33.

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1.33 sounds high for idle. Mine in offset+auto is about 1.05 at idle.

I'm running a 44x with offset at -0.010, idle voltage is .970 and maximum is 1.320

Edit: Playing around a bit more, now have 45x, offset +0.005. Idle still 970 and max 1.328

Forceman said:

1.33 sounds high for idle. Mine in offset+auto is about 1.05 at idle.

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I turn off EIST and C1E to determine the idle voltage at the turbo multiplier because otherwise you only see the full load voltage when it goes into turbo mode.

Interesting replies, but I still am not clear ?

I'd like to see the max overclock I can get with a peak of 1.375v into the CPU.

With my X58 board I would just set Allow VDroop and vCore of 1.375
and that would be the max voltage ever delivered to the CPU with any multiplier
and the voltage would drop as needed with speedstep.

With the P8P67 how can we input settings to limit to a specific max voltage
other than manual cpu voltage?

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Arkainium:
With EIST and C1E off does the bios report the correct base voltage?

With those on at 45x my bios was reporting 1.25v
and I set the offset to 0.04 hoping for under a 1.30 upper limit
but ended up with 1.38v under light load.

Puyol said:

With the P8P67 how can we input settings to limit to a specific max voltage other than manual cpu voltage?

Click to expand...

I think the closest you can get is to use offset and to make sure that load line calibration is disabled. Then you need to temporarily disable EIST and C1E/C3/C6 to determine how your offset effects the idle voltage at the turbo multiplier (I consider this the max voltage). Once you find a voltage you're happy with, you can re-enable EIST and C1E/C3/C6.

You need to do this every time you change the turbo multiplier because you have no control over the base voltage in offset mode. That's why I think it would be more useful to have the option to set the voltage manually for turbo mode and keep default voltages for non-turbo multipliers.

Puyol said:

With EIST and C1E off does the bios report the correct base voltage?

Click to expand...

I think the bios will always report the voltage for the default stock (non-turbo) multiplier plus the offset unless you set it to manual.

I am unable to keep even a weak overclock completely stable using offset, it always eventually fails/bsods during a minimal task. But with manual voltage set it is fine. I would really rather have the volts drop during idle but so far no luck.

Although the voltage stays the same with a manual setting, I've found that the actual current applied to each core drops during idle. I'm not sure how that is working or if it's even being reported properly, but ultimately current is what heats up/damages your processor, not voltage.

Run a hardware monitor and watch your watts and temps decrease to baseline at idle, even though it's reporting a high manual voltage. Makes me think that throttling *is* happening with a manual setting, it's just not being reported appropriately.