Setting vcore via offset vs manual - anyone do this?

[OrphanBoy]

Hi guys,

I'm not sure how many boards support this but I've seen some of the P55 boards with the option. I'd like to reduce the idle draw of my machine when overclocked and this option seems convenient. On my P7P55D my i5 750 will run rock-steady at 3.6GHz with a vcore of 1.2-1.22v ish. However, when Speedstep kicks in on idle and the multiplier drops down vcore remains the same.

If I set the voltage to 'auto' the machine appears stable but I'm not really sure how the voltage is determined, so I'm a bit wary of using it! It's definitely higher than the voltage at stock though. eg at 3.6 vcore is ~1.28v. When the machine idles vcore drops, along with the voltage.

When using vcore in 'offset' vs 'manual' mode with the offset at 0.1v, when one core is fully loaded it runs at 1.2v, four cores gives 1.24v.

Anyway - what's worrying me is the clock/multiplier change does not happen at the same time as the voltage change, and this appears to make the machine unstable. It will often step up from 1.8GHz to 3.6GHz but keeping the vcore at 0.9v for a several seconds...

Does anyone else use this offset method? Any info or advice?

Cheers!

 

[JonJ678]

If it's lagging between voltage change and frequency change leading to instability, consider the function not yet ready for use and try it again after a bios update or two.

I'd rather leave the idle voltage high than use something like this personally, I don't think the power savings from the change would be significant as processors use far less power at idle than at load anyway.

 

[dazzerd]

I use offset on my board no problem, may be a bios issue as suggested.

 

[OrphanBoy]

Cool thanks for the info - I might try it for a week or so and see how I get on!
I do wonder about the power draw on idle though Jon, surely one of the reason CPUs use less power at idle is because they drop the voltage down?

I do lack a power-measuring device...so I guess I can't test this!