Posts:
96
Registered:
Feb 21, 2006
|
|
|
|
Electonic "whine" from macbook pro when at idle
Posted:
Feb 21, 2006 6:56 PM
|
|
|
I got my 2.0GHz MBP today and I'm having a problem that is getting more annoying the more I use it:
When the computer is at idle, there is a "whine" that comes from under the keyboard. It sounds almost like there is a bad ground or interference.
As soon as one of the cores is maxed out or close to it, the sound goes away. As far as my tests have concluded, it is not a graphics engine problem, it is with the CPU itself.
Is anyone else having this problem? I am calling apple first thing in the morning, As I won't be able to use the machine for recording or anything similar because of feedback/noise.
(ps: it is not a fan, it is more like alternator noise in a car stereo)
Macbook Pro 2.0GHz Mac OS X (10.4.5)
|
|
Posts:
328
Registered:
May 28, 2005
|
|
|
|
Re: Electonic "whine" from macbook pro when at idle
Posted:
Feb 21, 2006 7:20 PM
in response to: sxs3200
|
|
|
I don't know much but i wouldn't think the cpu could make noise.
Hard drive
fan
screen
speakers (of course)
|
|
Posts:
95
Registered:
Jan 24, 2006
|
|
|
|
Re: Electonic "whine" from macbook pro when at idle
Posted:
Feb 21, 2006 7:24 PM
in response to: sxs3200
|
|
|
7200 rpm drive upgrade ?
They are slightly noiser then 5400rpm. Some being a lot noiser depending on brand/model. The higher speed causes a higher pitch as well. I have the stock 5400 and there is no noise.
All of them
Mac OS X (10.4.4)
|
|
Posts:
395
Registered:
Feb 18, 2006
|
|
|
Posts:
96
Registered:
Feb 21, 2006
|
|
|
|
Re: Electonic "whine" from macbook pro when at idle
Posted:
Feb 21, 2006 7:33 PM
in response to: leaknoil
|
|
|
120GB 5400rpm. Based on the sound and my hard drive usage (I'm using menumeters at the moment to check this out), it's not hard drive related.
Macbook Pro 2.0GHz
Mac OS X (10.4.5)
|
|
Posts:
96
Registered:
Feb 21, 2006
|
|
|
|
Re: Electonic "whine" from macbook pro when at idle
Posted:
Feb 21, 2006 7:35 PM
in response to: dliao
|
|
|
it is independant of any screen brightness (full bright to turned off.... the noise is still audible when I have the screen (back light) turned completely off.
Macbook Pro 2.0GHz
Mac OS X (10.4.5)
|
|
Posts:
175
From:
Seattle
Registered:
Apr 17, 2002
|
|
|
|
Re: Electonic "whine" from macbook pro when at idle
Posted:
Feb 21, 2006 7:47 PM
in response to: sxs3200
|
|
|
After working in the PC power chip business for 5 years, I'd guess it's a bad power supply design. The switching converters run at various frequencies and good designs avoid pulse widths that get near the audio range- down to 18 KHz, for example. Most are super-sonic, switching above the audio range. When they get down to lower frequencies, the electrical components will actually emit audio noise by acting as transducers (AKA: a speaker). The newer power circuit designs for RAM as well as CPUs and GPUs will do this. Most will vary the effect or frequency based on the load to the circuit.
The fix is a new design that will not get into this audible range.
PowerMac G5 & PowerBook G4
Mac OS X (10.4.5)
|
|
Posts:
1,571
Registered:
Sep 26, 2000
|
|
|
|
Re: Electonic "whine" from macbook pro when at idle
Posted:
Feb 21, 2006 8:03 PM
in response to: MegaBit
|
|
|
Does it happen when the MBP is on battery power?
12-inch PowerBook G4/867
Mac OS X (10.4.4)
AE, SD, 1.12 GB RAM
|
|
Posts:
23
Registered:
Feb 21, 2006
|
|
|
|
Re: Electonic "whine" from macbook pro when at idle
Posted:
Feb 21, 2006 9:34 PM
in response to: Alan Somers
|
|
|
I have the same Problem. Very loud whinning alomost all the time when idle. goes away a bit as i type.
MacBook Pro 2ghz
Mac OS X (10.4.5)
|
|
Posts:
54
Registered:
Oct 27, 2004
|
|
|
|
Re: Electonic "whine" from macbook pro when at idle
Posted:
Feb 21, 2006 10:11 PM
in response to: knewjax
|
|
|
It's not uncommon for electrical noise to be heard when idle, particularly if everything else is releatively quiet. I wouldn't worry about it, the machine is just doing it's job. I'm expecting mine on Thursday, so I'll see what it does. My G5 would always make noise when idle, but it wasn't ever enough to be picked up during a recording session or anything.
Here is a segment from the user manual:
"As you get to know your new MacBook Pro, you might hearsystem sounds during startup and when using your hard disk and optical drive. After the MacBook Pro runs for some time, small fans might turn on to cool it, producing a faint sound. System sounds such as these are part of the computer’s normal functioning."
Fan speed is controlled via pulse-width modulation. That could be part of it too. If the machine is stable, though, life is good.
MacBook Pro 2.0, Mac mini 1.25
Mac OS X (10.4.5)
|
|
Posts:
95
Registered:
Jan 24, 2006
|
|
|
|
Re: Electonic "whine" from macbook pro when at idle
Posted:
Feb 21, 2006 10:26 PM
in response to: sxs3200
|
|
|
Mine doesn't 'whine' at all. Totally stock 2.0 MBP other then a memory upgrade I did myself.
Have to put my head right to the keyboard almost to even hear the drive spining.
All of them
Mac OS X (10.4.4)
|
|
Posts:
96
Registered:
Feb 21, 2006
|
|
|
|
Re: Electonic "whine" from macbook pro when at idle
Posted:
Feb 21, 2006 10:42 PM
in response to: Alan Somers
|
|
|
both battery and power/charging... more so on battery (though perhaps that's because I was in a room that doesn't have other white noise.
Macbook Pro 2.0GHz
Mac OS X (10.4.5)
|
|
Posts:
96
Registered:
Feb 21, 2006
|
|
|
|
Re: Electonic "whine" from macbook pro when at idle
Posted:
Feb 21, 2006 10:46 PM
in response to: xenon
|
|
|
these are the weirdest fans I've ever heard then. It's not during startup or when using the hard drive or optical drive. I've never had a disk in the optical drive.
The sound is very digital, even if the fans were using stepper (sp) motors, they'd sound different.
Macbook Pro 2.0GHz
Mac OS X (10.4.5)
|
|
Posts:
2
Registered:
Feb 22, 2006
|
|
|
|
Re: Electonic "whine" from macbook pro when at idle
Posted:
Feb 21, 2006 10:47 PM
in response to: sxs3200
|
|
|
I'm hearing the whine on my MacBook too. Like others have described, it's only when the CPUs aren't active. I do *not* have the upgraded 7200 rpm drive, mine's 5400 rpms. It's definetly not the sound of a drive, not the drive, it's a high pitch almost like an unstable current flowing. It happens while using the battery or while plugged into the power supply.
-Nash
MacBook Pro Mac OS X (10.4.5)
|
|
Posts:
490
Registered:
Mar 20, 2004
|
|
|
|
Re: Electonic "whine" from macbook pro when at idle
Posted:
Feb 22, 2006 3:40 AM
in response to: bnash
|
|
|
Sounds like a bad power supply unit. If it goes away during cpu usage then goes up when idle. That makes most sense to me. Shame but I'm hearing an aweful lot of bad MBPs out there already. Could we have a Spruce Goose of a laptop on our hands?!
/gasp
20" iMac G5 2.1 - MBP 1.83 Intel Core Duo 2gb - Video iPod 30gb
Mac OS X (10.4.5)
|
|
|
