My MacBook Pro Sounds Like A Jet

bowjest

Registered
Hello to All,

I've just been doing some voice recording and have noticed two things:

1. I've had to turn up the mic sensitivity on my Edirol UA-25 about two ticks higher than normal (this would normally result in the vocal redlining in Garageband, but now it barely hits the middle of the scale)

2. I changed my performance settings from power saving to best performance and was prompted to log out and back in. I choose to shudown and reboot and after doing so, my MacBook sounded like a jet preparing to take off, then slowly faded to perfect silence (its normal mode of operation).

How worried should I be about this?

Thanks,

Bowjest
 
Don't worry at all about number two -- that's perfectly normal. If you have one of the MacBook Pros with the dual-graphics chipset, then by changing the Power Savings to "Best Performance," you enabled a more powerful graphics system on the MacBook Pro.

The fans that cool all this are controlled by the operating system. Before the operating system has loaded, the hardware defaults to running the fans as fast as it can for safety reasons. The operating system isn't monitoring temperatures yet, so the safest thing for the computer to do until then is run the fans full-blast.

By enabling another chipset, you increased the computer's need to cool various parts of the computer. That's why you might not have heard that fan ramp up like that until you changed to "Best Performance."

It's normal and expected behavior.
 
Diablo, one more thing if I may....

How hot should a MacBook Pro run? By that I mean, if I'm just doing emails and surfing the web, should the underside get fairly hot once it's been on for a while?

I've been doing mails and stuff for about an hour and a half and the underside of mine is pretty hot - but I haven't heard the fans kick in. Is that normal?

I've got it currently set on best performance, so would it really need to be grinding through some work for the fans to come on?

Sorry if this all sounds a bit paranoid, but the first MBP I bought last October had a major graphics fault and so they exchanged it for the newer model one with the black keyboard (nice!), so am just wanting to make sure everything is in order.

Thanks.
 
The MacBook Pro computers get "pretty dang hot," to put it most scientifically. The underside of the computer will get especially warm (read: hot) during periods of extended use -- even if it's "light" use, like web browsing.

Download the iStat dashboard widget:
http://www.islayer.com/apps/istatpro/
...or the menubar utility:
http://www.islayer.com/apps/istatmenus/
...they will help you keep an eye on the temperature of various system components. If any of them get above 200 degrees F and stay that way while you're doing light stuff, that may be cause for concern. I guarantee they will come close to 200 degrees F during normal use -- my MacBook sees 180 degrees F from time to time.

The fans will come on when they feel the need to come on. The widgets I linked to above also monitor fan rotational speed, so you can keep an eye on that. My MacBook's fans typically spin around 1,500rpm, and go through stages as my work load intensifies: 2,200rpm, 3,600rpm, and they top out at around 6,000rpm. They usually stay under 3,000rpm most of the time.

It sounds like the computer is operating completely normally. There's a reason Apple doesn't call them "laptops" -- using them on your lap is only for the sadochists of the world, and certain studies show portable computers in general heat up to levels that can cause discomfort and pain.

Apple recommends operating the computer on a hard, flat surface (no laps, no carpet, no bedding, no pillows) to ensure adequate airflow in and around the computer. Your best bet is to use the computer on a desk or table, and nowhere else (although some will debate the practicality of that).
 
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As always, Diablo, I greatly appreciate it. I've downloaded iStat as well as a great little tool called smcFanControl

It lets me turn up the fans if I feel the need.

I reckon that's a job well done. :D
 
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