View Full Version : [Solved] Interesting - 11" MBA no heat / fan noise, 13" very noisey, why?

Apr 26, 2011, 10:52 PM
Today I worked on an 11 and 13" MBA, both both are max'd out spec's, 'ultimate' as we say.

I had 9 web pages open, downloaded photo's from my camera to both machines, browsed the photo's with 'Just Looking' software, used VM Fusion with Win7 loaded on both machines used Microsoft Publisher, move some photo files in DropBox and also played back some 720p video clips ....the 11" is also currently plugged into a 27" ACD, the 13" is not...

The 11" is silent, I haven't heard the fans yet. It's amazing. With all these programs open the only lag I notice is on the 27" ACD when scrolling for example, it's a little choppy. Now, when I close out of Win7 it handles everything, no lag, no fan noise and not too hot.

The 13" on other hand roars doing the same tasks. I don't like that. From reading here I'm thinking it's normal for the 13" ... I could try a SMC/Pram reset I suppose. But I think it's just the way the machine is.

I wonder why? Also, is there something I can do to "safely" control the fan speed without doing damage to the machine. I'm not so sure on the software recommended and under volting etc, I'd rather not do that.

The fact the 11" is so quiet, even running windows is making it appealing over the 13" ... I hate fan noise.

Apr 26, 2011, 11:15 PM
I own a Core2Duo 13" MBP and it can get really hot and roar like that. Is the 13" Pro a i5, i7 or Core2Duo?

This is another factor that might get me from the 13" MBP line to to 13" MBA line :)

Apr 26, 2011, 11:18 PM
The 13" has a faster processer and bus speed. The 13" is LV (low voltage) while the 11" is ULV (ultra low voltage). It simply goes more in the same time and generates more heat. On the Geekbench application an Ultimate 11" gets a score of around 2500 while the 13" gets slightly over 3300. So you really see the difference on CPU intensive apps.

I've had both and have seen the same thing as you regarding fans. At full tilt the 13" is way noisier than the 11". But it goes get things done faster.

Apr 27, 2011, 12:24 AM
I installed Coolbook on my 13" just now. Will see how that goes. Any one else use Coolbook, what settings did you choose.

edit: 12 hours later; Coolbook solved the problem. Roaring fan noise gone. Was easy to install and set up to!