Custom Power Scheme not Throttling CPU

[BradJorgensen]

I'm working on deploying new Windows 7 pro x86 computers and I'm trying to get windows to throttle down the CPU when it can, but it isn't always working correctly. The settings for the power scheme that I want are basically highest performance on everything except the hard drive should turn off after 5 minutes of inactivity and the display should turn off after 15 minutes. Instead of reducing the CPU multiplier and parking 2 cores, it will run at 126% (the i7's speed boost thing) with all cores active.

More system info:
Processor: Intel i7 L620
OS: Windows 7 Pro 32-bit
Manufacturer: Coban
Model: M7
It might be something with the hardware since the computers are specialized units, but Coban isn't any help with this problem.

If I create a new profile with the desired settings, the CPU will be throttled usually until I restart the system. sometimes it works longer, but not much more than a few restarts. I have also tried exporting and importing a power plan between different computers and on the same computer and modifying the stock "power saver" plan, all with the same iffy results. The stock power saver plan always throttles down the CPU but only if it's in its default state.

I've seen a few other people with the same problem, but no progress towards a cause or solution. Any ideas?

 

[A Guy]

Welcome to Seven Forums BradJorgensen. I'm going to confirm you are using the advanced power options:

http://www.sevenforums.com/tutorials/778-power-plan-settings-change.html

Specifically the Processor Power Management and Maximum Processor State settings



Default for Performance is 100% for both (mine is set to balanced, hence the 5% default).

A Guy

 

[BradJorgensen]

Yes, I am using the advanced settings. 5% is the minimum state and 100% is the maximum state. I have tried using active and passive for the cooling policy.

 

[A Guy]

It is odd that the CPU would be clocked up when idle, perhaps that is the issue. It should at least be at stock speed. Cab you get into BIOS and confirm the various speedstep settings? A Guy

 

[BradJorgensen]

The BIOS is very minimal; there are no changeable CPU settings and it only shows some basic CPU information. I know there is hardware support for throttling since the power plan does throttle it when it is working.

 

[A Guy]

It's odd that it isn't even at stock clocks, but rather it is in turbo mode. Usually this only happens when the CPU is in use, and if it is indeed at 126%, then it is more then 2 cores in use. You are sure it is idling? Even with turbo boost off, it would run at the rated speed. A Guy

 

[BradJorgensen]

I am sure it's idling. I have been watching the resource monitor to see what it's doing. If I switch the power plan to the default power saver, the CPU immediately throttles down.

 

[kegobeer]

Download CPU-Z from cpuid.com and verify your processor is indeed running at full speed. I have an XPS15 with a Core i7, and the speed definitely stays low when I change my advanced power settings, even when running under high performance. Before you change the max processor setting, make sure you click "Change settings that are currently unavailable" just in case there's something going on in UAC that's preventing the change from being applied.

 

[Dave76]

@ kegobeer, that may be due to Dell's specialized BIOS settings, OEM's have a very controlled BIOS. Might be a laptop thing also.

On my custom build, High Performance will make the CPU run at full speed, frequency, all the time. The Balanced settings allows EIST, speed step, to work correctly.

@ BradJorgensen, try the Balanced setting and check if EIST is working correctly.
Does the default power saver, allow full power when needed?

 

[BradJorgensen]

I have already confirmed that it is at full speed with CPU-Z. The balanced plan does not reduce the speed. With the power saver plan, it does go to full speed if needed.