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CPU alert w/ Firefox - computer slowing, stalling - why? fix?


Am getting Alert - high CPU usage generated by FireFox - system slowing down, stalling. Is there a quick fix? HELP

Additional System Details

This happened

Every time Firefox opened

This started when...

Since December 1, 2011

Installed Plug-ins

  • nphpclipbook
  • Adobe PDF Plug-In For Firefox and Netscape "9.3.3"
  • Default Plug-in
  • Citrix ICA Client Plugin (Win32)
  • Office Plugin for Netscape Navigator
  • Shockwave Flash 10.3 r183
  • 4.0.60831.0
  • The plug-in allows you to open and edit files using Microsoft Office applications
  • Office Authorization plug-in for NPAPI browsers
  • Google Update
  • NPRuntime Script Plug-in Library for Java(TM) Deploy
  • Next Generation Java Plug-in 1.6.0_14 for Mozilla browsers


  • User Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv: Gecko/20091201 Firefox/3.5.6

More Information

David McRitchie 321 solutions 3089 answers

Not a fix but you might try avoiding large extensions that offer very little benefit. Also see if you have extensions mentioned in "Problematic extensions" and if you do read about problems that you may encounter and may have to make some adjustments for.

I would suggest installing the "Restartless Restart" extension (12KB and is for Firefox 4,0 and above) and perhaps invoking it when you leave the room so Firefox will be restarted where you left off when you return. Be sure to reply to any messages about closing tabs before leaving.

Since you are 3.5.6 instead install the "QuickRestart" (35KB) extension instead. You are on Windows 7 you can use the latest Firefox version 8.0, and 3.6.* would be better than what you have. Some of your problems might be lessened.

Modified by David McRitchie

  • Top 10 Contributor
  • Moderator
3193 solutions 24375 answers

Are you using AVG?

David McRitchie 321 solutions 3089 answers

AVG is reporting high memory usage levels not CPU usage on on the popup task bar messages that I see.