How to compensate for vdroop so idle voltages are lower than load

[I4AT]

I've had these parts laying around for probably a year, finally decided to throw the system together for some BF3.

i5 760, Gigabyte H57M-USB3, Windows 7 Home Premium 64

This doesn't affect the functionality of the system in any way, but it bothers me that my idle speed-stepped voltage is higher than my full load voltage.

My current settings are:

20x multi
160 bclck
CPU voltage ~1.174v in BIOS

Booting into Windows 7 CPU-Z will report between 1.152v and 1.184v, average 1.168v. Idle clocks are speed stepped down to 9x multi for about 1.44ghz.

Once I start Prime 95 Blend vdroop kicks in and the CPU ramps up to the full speed of 3.2ghz at 1.088v to 1.120v. I let the test run for about 6 hours last night with no errors.

Ideally I'd like the voltage to be lower when the machine is idle. It makes no sense to be running 1.44ghz at 1.168v when the CPU is capable of 3.2ghz at less than 1.100v. But obviously the default voltage needs to be set in the 1.17v range to account for the vdroop. I just wish EIST was smart enough to handle this at anything other than stock settings.

I could just use software like EasyTune to set up idle state and overclocked profiles and switch between the two as needed, but that's a pain in the ass compared to just setting and forgetting via the BIOS.

I tried Load Line Calibration and that just made the system hang immediately when Prime 95 was started. I think that's just intended to smooth out the voltage between idle and load states though, so that probably wouldn't help what I'm after anyways.

AFAIK there's no way to tell the BIOS use this voltage when the machine is idle, and use this voltage when the machine is under load. You'd think we'd have that level of control by 2010, but unless I'm missing something software overclocking from Windows = more flexibility, BIOS settings = more convenience?

 

[Deders]

LLC might be exactly what you are after, although I found I had to raise the voltage again once it had been enabled as on my 1156 machine windows reported it to be much lower than it said it was in the bios.

I'm still not sure which one is correct but I know once LLC was enabled it needed more initial voltage to be stable but overall when it's running at full tilt it produces less heat at lower voltages and (therefore lower power consumption) than it would when LLC was disabled.

You could probably get up to 3.8GHz without having to raise the voltage too high.

 

[I4AT]

I tried splitting my current min/max voltages and enabling LLC at around 1.140v or something in that range, and it just wasn't stable. This also isn't the latest BIOS release though so maybe that has something to do with it, but either way I think that would only help lower my current maximum voltage slightly (which is in the idle state), when my goal is to have the idle voltage be significantly lower than the load.

 

[Deders]

I have to run mine at 1.251 with LLC which is reported in CPUz as 1.272 Idle and 1.288 Load (It used to be reported at about 0.1v lower). It won't even boot at that voltage with LLC disabled.

Having your BLCK at 160 is kind of borderline for having to enable LLC or not but I think you'll get more consistent voltages with it enabled.

I don't suppose you have a wall plug to tell you how much power it's drawing at idle and load?

 

[I4AT]

Do you have EIST enabled? If so, when your multiplier drops does your voltage drop as well, or does it stick at ~1.28?

When my CPU is running 1.44ghz I feel like the voltage should be .090v or possibly even lower. Which is something that can easily be set with software. But then you end up having to micromanage everything with profiles, and it's just a nuisance.

Is there no way to customize EIST settings within the BIOS so that idle clocks = .090v, load = 1.174v?

 

[Deders]

EIST is set to auto but I presume it is enabled as my CPU drops to 1624MHz (1.272v) when idle although it's difficult to be sure as the CPU frequency fluctuates much more when CPUz is running according to Argus Monitor which also reports that the FSB stays the same at 180 whether idle or not.

 

[Deders]

Just measured my stock voltages and it runs at 0.888v idle and 1.112v load, a slightly larger gap than when it's overclocked with LLC but not a lot. Also just noticed in argus monitor it is my multiplier that changes like you say.

 

[john3850]

I believe after the 1366 Intel Management Engine controls most of the volts needed for the cpu operation.
With each new generation of cpus the mb has less control over the voltages.
If your into desktops this bad for moble users this is cool.
I have 2500k and 3770k and I almost no control over idle volts.
Both chips will run fine at 47-4800MHz with EIST off at fixed speeds.
With EIST and idle on I often get erorrs when going from idle to full load and back to idle.
It seems like the mb cant maintain a high enough idle
voltage.