SpeedStep Not Working

I have an Intel i5 and ASUS motherboard (on a desktop machine), and with Windows 8 I was able to implement Intel SpeedStep to slow the CPU when it didn't need to run at full speed. Updating to Windows 8.1 broke this, but I somehow got it to work again. Not it's not working again, and the only change to the configuration was a Windows Update for Intel Management Engine Interface that occurred on 10/25. SpeedStep is enabled in the BiOS.

Can anyone offer any advice? I'm not shy about registry hacks if necessary.

Have you tried uninstalling speedstep and then re-installing it? Sometimes that will do the trick.

bassfisher6522 said:

Have you tried uninstalling speedstep and then re-installing it? Sometimes that will do the trick.

Click to expand...

Intel SpeedStep isn't a program, it's enabled in the bios and Windows is supposed to use it automatically.

Well, SpeedStep has never been perfect and never will be
There are too many variables that can cause speedstep to never down the Core Voltage and Frequency
In some cases it can actually work backwards and never step back up when needed.
Personally, if there is ever a chance for me to turn it off I do. I set sleep modes instead.

Enhanced Intel SpeedStep® Technology - How To Document

Please Note:

To verify that Enhanced Intel SpeedStep Technology is enabled, do the following:

Close all applications and ensure that Windows OS is in idle mode.
(Note from me: Rarely will this ever be achievable, Too many things running in the background to achieve this level)


Press Ctrl + Alt + Delete and select the "Performance" tab.

Verify that CPU usage is 0. (This is almost impossible on todays PC's, see above)

Right click "My Computer" and select, "Properties."

Under the "General" tab, examine the installed processor and speed.

If Enhanced Intel SpeedStep Technology is enabled, two processor speeds will be listed.
The first speed listed is the specified speed of the processor.
The second speed is the current operating speed.
The second speed will be less then the first speed. (See Figure 1.)
This indicates that Enhanced Intel SpeedStep Technology
has effectively lowered the processor voltage and core frequency, which can (depending on system usage and design)
result in decreased average power consumption and decreased average heat production.

If Enhanced Intel SpeedStep Technology is off, then both processor speeds will be equal. (See Figure 2.)
If the processor is not in idle mode, Enhanced Intel SpeedStep Technology can be enabled and both processors speeds can be equal. If this happens, try steps 1-3 again.

After extensive testing I've determined that something changed from Windows 8 to Windows 8.1 with how SpeedStep is handled. Monitors show that the CPU speed does change, but only if Intel Virtualization Technology is disabled. This was not the case with Windows 8. I run Hyper-V for a virtual XP machine (I have two very old programs that won't run with anything but XP). With Windows 8 and the virtualization active the CPU monitors would correctly show step down to half-clock speed under low CPU load. With Windows 8.1 this does not happen. Further, power options for CPU clock settings are not available in Windows 8.1 with virtualization on but they were in Windows 8. I'm not sure what's going on, of if this is a real change in Windows 8.1.

Yet another update. Further testing using a CPU monitoring function that does not use Windows services (like CPU-Z) confirms that SpeedStep (and Turbo mode) in fact work with Hyper-V active. Windows apparently does not report the physical CPU clock but rather the virtualized processor speed for the host when Hyper-V is active which is why it doesn't appear that the CPU steps down or up.

I've been getting this error after updating to Windows 8.1. Does this error pose a threat of some kind to my system? Will disabling SpeedStep eliminate it? If so, how would I do that?