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Firefox 9 after a while starts using a lot of CPU power, need help!

  • 2 wótegronje
  • 7 ma toś ten problem
  • 1 naglěd
  • Slědne wótegrono wót JoeGP

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After a while (2 hours or more) firefox 9 (not the plugin container) starts eating up more and more CPU power, usually just to 25% (because usually i close it and restart it after that), but today i had work to do and i couldn't restart it right then and that resulted in firefix using about 50-60% of a 4 core 3.2GHz CPU (AMD Phenom II X4 955). I'm not doing anything extraordinary just writing emails and just plain normal browsing)

I only notice this because my CPU fan speeds up and makes a lot more noise if using more then 20% CPU power.

I'm pretty sure regular users wouldn't notice anything until it started to slow down their whole PC

I'm using Firefox 9.0.1 running on Win 7 64bit, i have about 20-30 tabs always open (loading) and i haven't tried disabling any add-ons.

I've read on forums that this might have something to do with flash data piling up, or with having to many tabs open.

After a while (2 hours or more) firefox 9 (not the plugin container) starts eating up more and more CPU power, usually just to 25% (because usually i close it and restart it after that), but today i had work to do and i couldn't restart it right then and that resulted in firefix using about 50-60% of a 4 core 3.2GHz CPU (AMD Phenom II X4 955). I'm not doing anything extraordinary just writing emails and just plain normal browsing) I only notice this because my CPU fan speeds up and makes a lot more noise if using more then 20% CPU power. I'm pretty sure regular users wouldn't notice anything until it started to slow down their whole PC I'm using Firefox 9.0.1 running on Win 7 64bit, i have about 20-30 tabs always open (loading) and i haven't tried disabling any add-ons. I've read on forums that this might have something to do with flash data piling up, or with having to many tabs open.

Wšykne wótegrona (2)

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Hi JoeGP,

Have you looked at the Knowledge Base article Firefox uses too much memory or CPU resources - How to fix or Firefox uses too much memory or CPU resources - How to fix? There is a lot of great information in there.

Hopefully this helps!

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It didn't show up when i searched for the problem on Google and it didn't show up when i search here on Firefox's support site either. And the reason it didn't because it's mostly not about my problem.

If' it was one of those things then i would have a high CPU usage the minute i opened my browser, but i don't. It will use a lot of CPU power (after a couple of hours) even if i don't do anything

And yes hardware acceleration is on and so is submit performance data and i use Ad Block Plus, and there isn't a correctly working theme or add-on out there that could use 50-60% of a 3.2GHz quad core CPU

I don't think this is something that can be fixed that easily