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Virtual PC vs. Power Management

It seems that people are constantly running into problems running Virtual PC on laptop systems with advanced power management. The reason for this is that Virtual PC is very demanding on hardware and has very strict timing requirements - and as each new revision of laptops comes along these systems perform more and more complex power management.

Problems start happening when these laptops tweak with things that we rely on. This can either be caused when the laptop changes the CPU frequency too often, or when the laptop actually powers down sections of the system that we are dependant on in order to conserve power. When this happens the user can see a variety of problems; ranging from sporadic pauses and bursts, virtual machines running too fast or too slow, repeated keystrokes or missing keystrokes to other timing related problems.

If you are seeing these problems you should:

  1. Install the laptop manufacturer’s power management tools. Sometimes using these to change the power settings can resolve the problem (though not always).

  2. Check for any bios updates available for your laptop. From time to time we work with laptop manufacturers to address issues we encounter as part of a BIOS update.

  3. If nothing else works - you can almost always solve these problems by installing Seti@home (or folding@home). These programs use 100% CPU running at idle priority, which means that they do not affect any other programs running on your computer - but they effectively stop the laptop from performing any power management.

Cheers,
Ben

Comments

  • Anonymous
    September 19, 2005
    The comment has been removed
  • Anonymous
    September 19, 2005
    The comment has been removed
  • Anonymous
    September 19, 2005
    Sorry. I should have asked if you have any more suggestions. I think that I have tried everything you suggested in your original post.

    Thank you,

    Mark
  • Anonymous
    September 20, 2005
    An update:

    I suspended seti@home because since I installed it, my CPU steps down from 1.7GHz to 600MHz within 30 minutes after I boot. IOW, it has the opposite effect on my system that intended.

    When I can carve a day or two out of my schedule I plan to do a theraputic reinstall of Windows. I don't know what else to do.

    Mark
  • Anonymous
    September 20, 2005
    Did you check for BIOS updates? IIRC, that solved some issues that were reported in the vpc newsgroup.
  • Anonymous
    September 20, 2005
    You can try RMClock: http://cpu.rightmark.org/products/rmclock.shtml

    [quote]Dynamic on-demand clock modulation adjustment is supported on:
    Intel Pentium M/Celeron M, Intel Pentium 4/Celeron (all cores), Intel Xeon (all cores), Intel Pentium D/Pentium Extreme Edition featuring On-Demand Clock Modulation (ODCM).[/quote]
  • Anonymous
    September 20, 2005
    Yes, I installed the latest BIOS update.
  • Anonymous
    September 20, 2005
    I visited the RMClock site. I don't understand how it could be configured to prevent the CPU slowing down. Can you explain?

    Thanks,

    Mark
  • Anonymous
    September 20, 2005
    The comment has been removed
  • Anonymous
    October 19, 2005
    The comment has been removed
  • Anonymous
    September 24, 2010
    i have a question... i'm doing a win7 lab and am trying to install a captured image using WDS and it's saying my processor speed is only 2mhz and need at least 750 or so... this is an i7 system that has been manually set to 190bclk X19... so auto steping SHOULD be disabled right?? since i have it manually clocked... don't know how to get it to recognize that it has plenty of Processor... literally i have it at 3.6 on air and the most it uses is 6% with 3 VMs running... any ideas? don't know if i'll find this site again... please completeitsolutions@cox.net