CPU clock scales down so computer is unusable after switching to battery

Posted by Ryan on Super User See other posts from Super User or by Ryan
Published on 2012-09-20T13:55:24Z Indexed on 2012/09/20 15:41 UTC
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cpu

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power-management

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laptop

When I am plugged in my laptop runs great however when I unplug it and I'm on battery power my CPU clock speed scales down pretty much all the way.

I know this is happening by monitoring the clock speed. When plugged in it will usually stay between 1000MHz and 3000MHz but when I unplug it it quickly scales down to less than 500MHz and will get as low as 100MHz and it will NEVER scale up at all on battery power. After I plug the power back in it will then begin operating normally in about a minute.

I have tried setting the MIN and MAX CPU performance in power options to 100% and have tried messing around with cooling settings which seemed to be a problem with HP laptops. I have a Toshiba Satellite M500-ST6444 running Windows 7. The BIOS is up to date. I have tried two versions.

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