Firefox 4 Fan Overheating Issue

Hey guys! Just wondering if anyone here can help with something (or have heard other Mac users complaining about this).


I've been a Google Chrome user for the past 2 months now and love it! Except, some websites still aren't compatible with Chrome so I've been looking for a good alternative.


So Wednesday I decided to download Firefox 4 and give it a spin. And everything has been great.....except one thing. Whenever I use FF4 and go to any website that plays videos, my fan kicks into high gear. I'm talking about simple things like watching a vid on YouTube or watching a couple of vids on NFL.com for example.

The thing that puzzles me is I NEVER have this problem when using Chrome. The fan never kicks on when watching vids so I'm assuming this is an FF only issue. Have any of you guys on here have this problem?

The term "overheating" is often used inappropriately. Much like with a car that is overheating, a computer that overheats shuts down and is unusable. Your Mac is designed to run hot when the CPU/GPU is under load. So although this may not be comfortable on your lap (note that it's not intended to be used there), it is not "overheating".

Firefox now has capabilities that offload processing to the GPU to render pages more quickly. Although I have not had this particular problem, some have suggested running Firefox in 32-bit mode in order to avoid these kinds of issues. This is done by right-clicking the Firefox icon (not the icon in your Dock, but the one in the Applications folder) and clicking "Get Info". Then check the box marked "Run in 32-bit mode" and see if the problems persist.

If they do, you can also turn off hardware acceleration, which is an option in Firefox Preferences, under Advanced => General tab, in the Browsing section.

Thanks for your help cwa, I'll try that and see if I still have problems.

Well, after testing it out on 32-bit and turning off hardware acceleration....my fan doesn't kick on anymore but video seems a little choppier than before. Is there any way I can run FF4 at 64-bit and have hardware accel on but not have the fan issue??

I'm curious to know if you saw any video issues using Chrome? What other plug-ins do you have running on FF. Mozilla just released a list of poor performers Slow Performing Add-ons.

Crank up the CPU, set the GPU to hardware acceleration and shut down the fan - now you will have overheating issues.

The problem isn't Firefox -- it's FLASH. You have just discovered why Steve doesn't allow it on mobile devices.

For YouTube, switch to the HTML5 implementation by default (there's probably a plug-in for that, I use one for Safari). Problem solved.

BrianLachoreVPI said:

I'm curious to know if you saw any video issues using Chrome? What other plug-ins do you have running on FF. Mozilla just released a list of poor performers Slow Performing Add-ons.

Click to expand...

No, I'm using Chrome now and I never have problems with my Mac getting hot when watching vids.

chas_m said:

The problem isn't Firefox -- it's FLASH. You have just discovered why Steve doesn't allow it on mobile devices.

For YouTube, switch to the HTML5 implementation by default (there's probably a plug-in for that, I use one for Safari). Problem solved.

Click to expand...

A little confused, are you saying I should look for a Firefox add-on that switches to HTML5?

cjjr72984 said:

No, I'm using Chrome now and I never have problems with my Mac getting hot when watching vids.

Click to expand...

I was just curious since you said the video was choppy after following cwa's advice to disable hardware acceleration. Just wanted to make sure you hadn't had any problems running all that flash with just the processor. That leads me back to any overly laborious FF add-ons you might have running - which is why I posted that link. Perhaps you have some add-ons that are really taxing the performance of FF - causing the choppy display?

I mean - if you don't have the problem with Chrome - and it's running CPU only, no help from the GPU - but when you switch to FF it kicks in the GPU - runs fine but you don't like the extra Watts put out by the GPU - so you go back to just CPU (as in Chrome) - to me that all points to sluggish FF performance. Since the new version of FF seems to be, by all accounts, a much improved performer than the 3.x versions - then that seems to point to something slowing FF - which is why I suggested you look at your add-ons.

You might want to look into changing the time between session saves in Firefox by following the instructions here. It seems that for some, when the session is saved, it negatively affects Flash video performance