smcFanControl — Cool Your MacBook Pro 195
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."
Well, it works ... (Score:3, Informative)
I wonder how it works, I'd love to see the source code for it
Re:My pref... (Score:2, Informative)
* At least, I believe it will, a lot of other PCs do, and my old mac did
Re:Well, it works ... (Score:1, Informative)
Speedfan for Windows (Score:1, Informative)
Re:Uh huh (Score:5, Informative)
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:Well, it works ... (Score:5, Informative)
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, it works ... (Score:1, Informative)
Re:Uh huh (Score:5, Informative)
fan failure, not battery life, the issue (Score:5, Informative)
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.
Thermal Management For Laptops (Score:5, Informative)
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:Uh huh (Score:3, Informative)
Re:Well, it works ... (Score:2, Informative)
It is inside the
Also
Peace,
Donald
Re:Uh huh (Score:5, Informative)
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:Thermal Management For Laptops (Score:5, Informative)
Re:fan failure, not battery life, the issue (Score:5, Informative)
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:Uh huh (Score:4, Informative)
Basically, fans can be fed anywhere from 0 to 12 volts (maybe laptops are 0-5v, but it's pretty standard). It usually takes 5-6v to get them spinning and overcome inertia, but after that you can drop it down to 4v or so to keep it going. The app just overrides the software control telling it to throttle the voltage until it hits near a certain RPM. The voltage control almost certainly works on a percentage, but even if not, there's only so much available to give it - you can't just pull random extra voltage in from somewhere to overvolt the fan.
As to the relation to a hard drive... couldn't say. I've seen numerous desktop-sized fans that use quite a bit more power than a notebook hard drive, which (in my experience) draw 2.5w or less (ie, you can power them from a USB port with no extra plugs). There are fans out there that draw 12w and up, but those tend to be the high-speed 120mm fans that can do serious damage to objects that happen to get in their way. Notebooks, on the other hand, tend to use very small fans such as 40mm units, which have a power draw in the half-watt range at full tilt. Varies by fan of course, but this probably won't drain your battery any faster than plugging in a flash drive and pulling a few files from it.
I'm just a bit irked that Slashdot posted this today. Not 36 hours ago, I left my MBP at the Apple store for them to fix the heat problems.
Re:You think it would work correctly from the fact (Score:1, Informative)
People will complain when their laptops only works 2 hours on a charge. You can then increase the battery size, but then people will complain when their laptops weigh 5 pounds and is 3-inch thick. People will always complain and tradeoffs will always be part of the design.
Re:Uh huh (Score:2, Informative)
A 1 inch miniature fan uses about 60mA at 12V. So running at full tilt, it consumes about 0.72W of power. The minimum setting where it will still start reliably, is about 6V at 50mA, so the power is about 0.3W. So, from that you can see that the power consumption of miniature fans is negligible - almost nothing.
The performance of the little fans vary a lot, but the power consumption of even the worst fan I measured, is still negligible. I am actually typing away on this little machine right now, and I think one fan needs a bigger resitor - still too noisy - need to turn the soldering iron back on...
Re:fan failure, not battery life, the issue (Score:3, Informative)
With all fans dead, temp reached 92C, but the system DID NOT FAIL. It _did_ clock cycle to keep running, but I could not get it to freeze up.
Too bad that is just a hack... (Score:3, Informative)
I was just looking at it... (Score:3, Informative)
Re:Yes: PowerBook (Score:2, Informative)