smcFanControl — Cool Your MacBook Pro

Clodas writes, "smcFanControl 1.1 is a simple GUI that lets you control how fast each fan spins on your MacBook, MacBook Pro, or Mac Mini. The temperature of my MBP when idle averaged around 63 degrees celsius. After running smcFanControl 1.1, my temperature dropped to 43 celsius within 10 minutes of use. This now allows me to sit my MBP on my lap, something I was unable to do previously since the machine got so hot. I have my fans set to spin at a minimum of 3000 RPM and I still don't hear the fans spinning. Apple by default has them set to 1000 RPM. I really recommend smcFanControl 1.1 for any that feel their MB, MBP, or Mini are too hot to handle."

Comments

Finally!

[TPIRman]

I really recommend smcFanControl 1.1 for any that feel their MB, MBP, or Mini are too hot to handle.

Finally! I can use my Mac mini on my lap again.

Uh huh

[nodwick]

I have my fans set to spin at a minimum of 3000 RPM and I still don't hear the fans spinning. Apple by default has them set to 1000 RPM.

And how long does your battery last between recharges now?

Re:Uh huh

[dal20402]

Been using smc and then smcFanControl since they showed up... battery life on my MBP doesn't seem appreciably different, not that it was any good to begin with, with the 7200rpm HD.

The best way to save battery is to dim the screen. At less than half brightness I can get nearly 3.5 hours in normal usage. At full brightness it's more like 2.5+.

Re:Uh huh

[kloppe]

A fan's power draw is a couple of watts at most, and no, your fan won't die 'orribly from it using speed control software. :) Higher speed probably means the bearings will wear out a bit faster though. For more info, check out http://en.wikipedia.org/wiki/Pulse-width_modulatio n

Re:Uh huh

[dal20402]

Yes.

If your screen buzzes when dim you have a bad inverter board. Unlike the famous CPU whine, Apple was willing and able to fix this problem from the very beginning. If your machine has the bad inverter, send or take it back to Apple for repair.

Re:Well, it works ...

[dal20402]

There's no benefit in setting fan speed to 6000 at idle. Here are idle CPU1 temps for my MBP (after it's been running for at least 20 mins) at various speeds. Each MBP tends to get different results, so YMMV.

Default (1000rpm): 59-62 C
2000rpm: 49-51 C
2500rpm: 46-48 C
3000rpm: 42-44 C
3500-6000rpm: no change: 38-41 C

Note that the faster speeds DO make a difference when the MBP is doing intensive work, as it appears that setting the minimum speed to higher also causes the fan to ramp up more quickly. At sustained 100% CPU load the machine is always hot but the lowest temperature was reached when I set the minimum to 5000rpm: about 78-81 C.

On the outside, the machine is MUCH cooler when using any setting over 2500rpm. It really is a "laptop" now. And below 3000rpm the fans are barely audible. I don't know what Apple was thinking when they chose such a low default.

Re:Well, look at it this way.

[Mooga]

Does fertility really matter? I mean, we're posting on SLASHDOT. If we had a life, we wouldn't need to post about cooling our laptops on slashdot...

Undervolting

[Aardpig]

I think it would be even better if you could unvervolt the MBP. My 2.26GHz Pentium M Sonoma system used to run very hot (95C) under full load (e.g., mprime); by undervolting from 1.35V to 1.18V, I've cut that down to 75C. Not only does this solve a heat problem; my fans are also quieter (since they are under less stress), and I have a substantial power saving to boot (recall, power consumption scales as voltage squared).

1000 posts. Hmmm, maybe I should get out more...

fan failure, not battery life, the issue

[SuperBanana]

And how long does your battery last between recharges now?

The question is whether the fans will be run past their expected/rated lifetime before the computer has.

As we all know- small fans (CPU fans, chipset fans anyone?) don't last very long. That's precisely why they're only run when necessary. Given the MB/MBP's thermal output, Bad Things will happen if those fans fail- probably no worse than it shutting itself down or crashing. Still won't be good for it.

That said, keeping the fans on a very low speed to maintain a cooler temperature will improve general component life.

Re:fan failure, not battery life, the issue

[TubeSteak]

The question is whether the fans will be run past their expected/rated lifetime before the computer has.

As we all know- small fans (CPU fans, chipset fans anyone?) don't last very long.

Computer fans generally die out because they use shiatty oil impregnated sintered bronze bushings. Bushings soaked in oil are vastly inferior to a good sealed bearing.

Though heat is still an issue either way, since it'll degrade the lubricant, bearings will have a longer lifespan without maintanence.

You can revive a noisy computer fan if you peel back the sticker & put a drop of oil into the hole, but no promises on how long that'll last.

This might also resolve the "it won't spin up" problem, though sometimes that's just the motor dying & not the bushing sticking.

Re:Well, look at it this way.

[elmarkitse]

The 'decrese in fertility' is totally unrelated to the temporary discomfort of burning your wanker by having something too hot sitting on it.

Do a google search for "intra scrotal temperature fertility" and you'll find all kinds of interesting tests that basically say that heat messes with how the dna in your sperm is formed. An increase in heat doesn't damage what you've got, but your newly forming sperm goes 'all out of whack'

Also, wearing tight underpants is worse the boxers or commando, and sitting is worse that walking.

http://www.reproduction-online.org/cgi/content/ful l/129/4/505

http://humrep.oxfordjournals.org/cgi/content/abstr act/20/4/1022

Only fix, I suppose, is to get your computer off your lap, strip naked, stand up, walk around, and eject any damanged sperm. You can just tell whoever walks in that you're busy saving the human race.

Thermal Management For Laptops

[loose electron]

I designed the chip for something called TAFI (Temperature and Fan IC) a way back. This widget (or a variation on it) now sits inside every PC/Mac/Laptop/Desktop box on the planet that has variable speed fans, that cool on demand.

How it works (the simplified 2 mile high view)- Sitting over inside the microprocessor is a diode, that is at the same temperature as the microprocessor chip. The forward biased voltage of a diode changes with temperature. With some signal processing, you can turn that into a temperature number.

The temperature is available for readback over a serial bus. (SMA,SMB, I2C, the original was SMA if I remember correctly) A software routine reads the temperature and makes the call "cool me off" or "at desired maximum temperature" which gets turned into a number that gets loaded over the bus back to the TAFI chip. That number gets dumped into a DAC, which becomes the voltage for powering the DC motor fan.

Presto! Variable speed fans dependent on how hot the microprocessor is!

Before that, all the PC's had fans that ran full blast 24-7-365.

Whoever did the software better realize that they are messing with the thermal management system and could seriosly fry their computer, if they set things up to not cool enough. So like any hardware hack, YMMV and you are taking a chance of doing permanent damage to the machine.

The fan motor, in comparision to the processor, does not suck that much juice, so I expect that it won't change battery run time in a big major way. A little, but not gobs.

Re:Thermal Management For Laptops

[Khuffie]

This only changes the 'minimum' speed your fan runs at; if the cpu gets too hot, the machine will automatically increase the fan speed above that as needed. It's just that the minimum speed on my MacBook is at 1500, and it lets me adjust that (it doesnt allow me to go below that).

Re:Well, look at it this way.

[BKX]

The proper term is "receiver." (Yes, it's safe for work, and much funnier than the original.)

Re:Well, it works ...

[mustafap]

>I would pay for this app if it was a commerial program!

The source is GPL, so you can buy it as a commercial program. Please feel free to post your credit card details, and I'll sell it to you for the bargain price of $49. I'll even ship you the source code!