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firefox 39.0 is using to much cpu what can i do to fix it?

  • 3 replies
  • 3 have this problem
  • 24 views
  • Last reply by seeclear

chris600
chris600
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okay so the cpu usage spikes alot when i am not doing anything but when i watch youtube videos it sometimes spikes up to 70 but mostly in the 50s

okay so the cpu usage spikes alot when i am not doing anything but when i watch youtube videos it sometimes spikes up to 70 but mostly in the 50s

All Replies (3)

agucova
agucova
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chris600 said

okay so the cpu usage spikes alot when i am not doing anything but when i watch youtube videos it sometimes spikes up to 70 but mostly in the 50s

Please see: Firefox uses too many CPU resources - How to fix

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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You can try to disable hardware acceleration in Firefox.

  • Tools > Options > Advanced > General > Browsing: "Use hardware acceleration when available"

You need to close and restart Firefox after toggling this setting.

You can check if there is an update for your graphics display driver and check for hardware acceleration related issues.

seeclear
seeclear
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I have done all the suggested things to reduce FF CPU usage, and none of it works. FF is just too bloated! It's always using 100+ of my CPU, causing my fan to be on all the time (MacBook Air 2012), even when in the background.

Only when I quit FF does my fan turn off.

Mozilla really needs to rewrite this thing from scratch.