There is a simple solution to this: Turn off Hardware Acceleration. However, in version 32.0 this seems to be excessive and in the case of smaller laptops or notebooks that have medium to high spec graphics cards it causes those cards to heat up and thus force the fans to go into jet engine noise mode.

If you visit a page that uses Javascript, or Flash then Firefox will attempt to utilise the spare capacity of the graphics card in order to save CPU usage! Firefox can grab hold of the graphics card hardware in order to make webpages load and run faster. With Firefox version 32.0 The noisy fan problem is connected with the graphics card. This is perfectly normal and should not cause the fans to spin up. Note that System Idle Process should be near 100% and firefox.exe should be around 0-5% (higher if you have many tabs open or have slower hardware). In Windows you can test this by going into Task Manager (quick access tip: Press Ctrl-Shift-Escape all at the same time) and viewing the Processes Tab. But with this update high CPU is not the problem. Sometimes when Firefox is updated there can be incompatabilites with add-ons (the tools for blocking ads, stopping spyware, etc.) The add-ons can cause excess memory usage problems and thus force the CPU and the fans to run fast. Incompatible Add-Ons Can Cause High CPU Usage But in this case the CPU usage was normal and it was the way Firefox uses the graphics card that caused the noise issue.

The hardware senses that the laptop needs to run fast and then automatically cranks up the fan speed a notch or two. Usually this happens when the CPU usage goes too high. Today I updated Firefox to the latest version (32.0) and noticed that the laptop fans spun up to an unacceptably loud level.

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