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I am using windows 7 64-bit, after updating firefox to v33.1.1, it significantly slows down my computer. It worsens if I use Flash v15 at same time

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  • Last reply by FredMcD

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My CPU usage keep at close to 100% whenever I open firefox with or without flash, of course it is nightmare with both on use together. Don't have this problem with my other computer using windows 8.1. Can you help me solve this problem please? Thanks.

My CPU usage keep at close to 100% whenever I open firefox with or without flash, of course it is nightmare with both on use together. Don't have this problem with my other computer using windows 8.1. Can you help me solve this problem please? Thanks.

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Hello,

Can you try creating a new profile and seeing if your CPU utilization is also high? Please see Profile Manager - Create, remove or switch Firefox profiles for information on how to create and select profiles.

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Start Firefox in Safe Mode {web link} While you are in safe mode;

Type about:preferences#advanced<Enter> in the address bar.

Under Advanced, Select General. Look for and turn off Use Hardware Acceleration.

Poke around safe web sites. Are there any problems?

Then restart.