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MikeD · Oct 20, 2010, 10:24 PM

I have an original 2.8ghz C2D MBP (5,1) and I hear the fan all the time. It's not BLARING but I do hear it and it's definitely not silent. iStat widget is saying my fans are running at about 2000 or so RPMs. Now, I was just wondering how you guys with newer MBPs are doing as I've been thinking about doing an upgrade within the year.

imitchellg5 · Oct 20, 2010, 10:40 PM

You must have sensitive hearing. All MBPs idle at 2k RPM.

MikeD · Oct 20, 2010, 11:00 PM

So is your MBP virtually silent? I took a quick little recording with the iphone voice recorder and it sounds a lot louder in this file than it does (probably since the mic of the phone was by the left speaker area). It's just been bothering me lately...

Here's a link to the m4a file...

https://files.me.com/biosci/lxjwep.mov

stratmaster458 · Oct 21, 2010, 08:50 PM

My MBP is only crazy loud when I used SMC to crank the fans to 6K RPM, which is most of the time because I want to keep temps between 40-60 C

imitchellg5 · Oct 21, 2010, 10:04 PM

Originally Posted by stratmaster458

My MBP is only crazy loud when I used SMC to crank the fans to 6K RPM, which is most of the time because I want to keep temps between 40-60 C

Um, why?

stratmaster458 · Oct 21, 2010, 10:26 PM

Originally Posted by imitchellg5

Um, why?

because I care about the well being of my CPU and high temperatures will destroy a CPU. Also having the CPU operate at high temps will hinder peak performance, my studies as an engineering student and a semi-professional recording enthusiast require as much performance as I can get out of my machine so I take care of my hardware by keeping it cool. I am not an average mac fanboy, I have been on the platform all my life not a n00b who switched over after the intel switch, I have a considerable knowledge of computers in general and I am well versed in Mac OS X, OS9, and Windows.

MikeD · Oct 22, 2010, 11:23 PM

I wonder if this annoying fan thing on my computer could warrant an applecare repair... It just bothers me with fans on in computers that make sounds. I had that in my old G5 Tower so after some 4 years of use, I switched to the macmini and actually like the silence of it all! I'm thinking about the new macbook air too but may want to hold off until the next revision / speed bump. Sigh..

AKcrab · Oct 23, 2010, 12:32 AM

Originally Posted by MikeD

Here's a link to the m4a file...

I don't think anyone took the time to listen to the file..

That's a fan that needs replaced. Take it to a shop.

imitchellg5 · Nov 4, 2010, 02:11 PM

Originally Posted by stratmaster458

I am not an average mac fanboy, I have been on the platform all my life not a n00b who switched over after the intel switch, I have a considerable knowledge of computers in general and I am well versed in Mac OS X, OS9, and Windows.

Congratulations; you don't think that Apple are intelligent enough to figure out the correct temperatures to keep a computer cooled at? My MacBook Pro's fans have NEVER even gone above 4k RPM, I have no idea why you'd want to put up with the noise of them running at 6k RPM.

P · Nov 4, 2010, 07:45 PM

Originally Posted by stratmaster458

because I care about the well being of my CPU and high temperatures will destroy a CPU.

Correct in theory, but any recent processor has functions to prevent that from happening. It will throttle down and finally even shut down if required to keep the CPU working. Even if you remove the heatsink while running, the CPU will shut down to save itself. Laptop CPUs are designed to run at higher temperatures. While there is a rule of thumb that desktop Core 2s should be kept below 60C at all times, that doesn't apply for the mobiles. Tcase (the temperature for when throttling starts) is 61.4C on desktop Core 2, hence the rule. Intel doesn't specify throttling temperatures for mobiles, as it is a bit more complicated, but they do set TJunction Max at 105C for your CPU, and Tcase is generally 10-15C lower, so throttling starts at about 90C. Keeping a mobile at less than 60C will just stress the cooling system for zero gain.

All of this data is available at ark.intel.com, if you're interested.

Originally Posted by stratmaster458

Also having the CPU operate at high temps will hinder peak performance, my studies as an engineering student and a semi-professional recording enthusiast require as much performance as I can get out of my machine so I take care of my hardware by keeping it cool.

You don't gain any more performance by keeping the CPU extra far below the throttle temperature. There is absolutely no reason to increase fan speed to gain performance. The reason for using smcfancontrol is that the bottom of the computer can get uncomfortably hot otherwise.

(The situation is slightly more complicated for newer Core iX chips, but let's leave that aside for now).

Originally Posted by stratmaster458

I am not an average mac fanboy, I have been on the platform all my life not a n00b who switched over after the intel switch, I have a considerable knowledge of computers in general and I am well versed in Mac OS X, OS9, and Windows.

That's nice. I can't say the same, because neither the Mac nor Windows did exist when I was born. I started using Macs in 1985, for all that that matters.