Does the CPU need to support SpeedStep in order for Power Saver profile to reduce the CPU frequency? RRS feed

  • Question

  • I'm confused why I have the options of Balanced or Power Saver if the CPU I'm using isn't supporting SpeedStep.

    I use the Intel board D510MO. This board doesn't support SpeedStep. Why am I seeing the 'Maximum Processor State' in 'Processor Power Management' in advanced power options on Windows 7. Does seeing this option mean Windows can reduce the frequency? If so then why there is no effect on the processor frequency if I limit the 'Maximum Processor State' in 'Processor Power Management' in advanced power options?

    Maybe it is a bug in Windows 7. If the hardware doesn't support reduction of the processor frequency theSubmit 'Maximum Processor State' in 'Processor Power Management' should not be available.

    Saturday, August 7, 2010 11:08 AM

All replies

  • 'Maximum Processor State' is not related to SpeedStep. Configuring the maximum and minimum process states limit the CPU performance status. If you are interesting, please read the following blog.

    Configuring Windows Server 2008 Power Parameters for Increased Power Efficiency

    Please remember to click “Mark as Answer” on the post that helps you, and to click “Unmark as Answer” if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread. ”
    • Marked as answer by Arthur Xie Friday, August 13, 2010 9:43 AM
    • Unmarked as answer by melmar Friday, August 27, 2010 12:53 PM
    Tuesday, August 10, 2010 9:04 AM
  • In the article you recommended to read only P states are discussed. My CPU doesn't support P states as can be seen on the output created with powercfg -energy. Throttle states are supported but the article doesn't mention throttle (T) states. The CPU on my desktop computer is still constantly running at 100% Maximum frequency even though the CPU load is constantly below 5% for hours and my power theme is 'Power saver'. With exactly the same settings on my laptop the CPU frequency is manged perfectly by Windows. I used the Resource Monitor to monitor the CPU frequency. Should the processor with the following power management capabilities be able to throttle the CPU speed if the CPU usage is below 5% for a prolonged time? What is the difference between T-states and P-states?


    Platform Power Management Capabilities:Processor Power Management Capabilities
    Effective processor power management enables the computer to automatically balance performance and energy consumption.
    Group 0
    Index 3
    Idle (C) State Count 1
    Performance (P) State Count 0
    Throttle (T) State Count 8


    Friday, August 27, 2010 1:18 PM