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Penryn MBP LCD Brightness Whine?

I have exactly the same problem and am annoyed as @#ll.. I always used windows machines and decided on buying a $$ MacBook Pro for it's multi OS and good critics on hardware. Now I can't use my good old XP without getting stressed out on a high pitched whizz wich penetrates my inner cortex. Here are my hardware specs: I have ForceWare driver 167.63, BIOS 60.84.49.03.00 on a 2.6 CPU and 17" screen
 
I'm getting the complete runaround from apple support about this. I called, they wouldn't take my word about whether or not this was a real problem, could not find any official cases recorded of this on their support line, would not create any record of any kind for investigation by a team of theirs. Essentially, there was no way to move forward, they weren't even willing to look at these forums or their OWN at:

http://discussions.apple.com/thread.jspa?messageID=6849995&tstart=0

Because we, the people, are perceived to be retards and none of this indicates a verifiable problem.

Typical call center idiot-rep BS (I worked in a call center a long time ago, used to this). "Blah blah, it's not our problem because it's related to windows, call microsoft and talk to them.". "Yeah, we shipped the software to you on the max osx cds, but its not supported."

The nvidia site doesn't have any drivers that I have been able to find to update what was supplied with the CDs to test the driver theory. The ONLY drivers I can locate for this hardware are on the OSX cds.

Not sure what to do...
 
This is what NVIDIA says on their website:

NVIDIA GeForce 8600M GT 167.63 The manufacturer of this system requires that you download the driver for your GPU from their support site.

The GeForce M series and GeForce Go series notebook GPUs use drivers that have been customized by the notebook manufacturers to support hot key functions, power management functions, lid close and suspend/resume behavior. NVIDIA has worked with some notebook manufacturers to provide notebook-specific driver updates, however, most notebook driver updates must come from the notebook manufacturer. Additionally, the desktop GeForce graphics drivers will not install on Geforce M series and Quadro M series notebook GPU's.




Soooo, Apple must respond to this, and NVIDIA has nothing, and will supply nothing to fix this. Help please.
 
Okay i called apple back and got someone who was not a douche, and they were a lot more helpful too. I tried the above fix in Vista 32bit and it doesn't work.

+ Apple is aware of this problem and there are a lot of people complaining.
+ They are working on a software update fix, might be available by the end of the month.
+ Sit tight and wait for it.

Generally i'm OK with waiting for now, since Vista really does kind of suck and I don't want to spend a lot of time there as is. Another thing that sucks, my MBP has 4G of ram and Vista 32 bit addressing can only see about 3G worth, and that is by design. Honestly, i just assumed we would have moved past that with XP but nooooo. Awful.
 
good, because reverting to the old drivers as posted in the other thread didn't work for me either in XP....
 
Is this damaging my machine?

So, from the above i understand that this is a software/driver issue. It seems that we have the current Nvidia drivers, and it is happening in Vista and XP via BootCamp from santarosa up.

I am assuming then, that Bootcamp Controls some of the navigation when it comes to accessing these drivers(GeForce 8600s). Is this making the fans in the GPU spin/whine like crazy? I am guessing this would be a Bootcamp software hick-up. Is this over stressing my Graphics Card, with respect to medium user load and 4/5 brightness? Why the brightness levels? it must be the fans, more stress results in more heat= fan RPM increase

I have a 2.5 GHZ 7200 MBpro with wXPsp2pro retail.
 
no, it's not the fan, its more like you can hear the IC' switching on and off very fast to dim the screen, more or less like a dimmer works on a lightbulb. The dimmer cuts the power to the bulb at a very high frequency so you can't see it going on and off but it appears to be dimmed. To dim the light more, a bigger part of the power is cut off in this high frequency pulse. Maybe the OSX uses a different frequency for this 'Pulse Width Modulation' which is less audible, just guessing here...
 
grit said:
no, it's not the fan, its more like you can hear the IC' switching on and off very fast to dim the screen, more or less like a dimmer works on a lightbulb. The dimmer cuts the power to the bulb at a very high frequency so you can't see it going on and off but it appears to be dimmed. To dim the light more, a bigger part of the power is cut off in this high frequency pulse. Maybe the OSX uses a different frequency for this 'Pulse Width Modulation' which is less audible, just guessing here...
Click to expand...

Ahhhh, this is why the brightness buttons alter the noise.Thanks :D. SO, do you suppose this "dimmer" is being stressed by this pulse width?

Should I not use Bootcamp, as a precaution, to prevent hardware damage?
 
grit said:
no, it's not the fan, its more like you can hear the IC' switching on and off very fast to dim the screen, more or less like a dimmer works on a lightbulb. The dimmer cuts the power to the bulb at a very high frequency so you can't see it going on and off but it appears to be dimmed. To dim the light more, a bigger part of the power is cut off in this high frequency pulse. Maybe the OSX uses a different frequency for this 'Pulse Width Modulation' which is less audible, just guessing here...
Click to expand...

Good theory, however, if this had to do with the modulation of the power sent to the LED backlight, would it not peak at full brightness; i.e. max load on that circuit? Also, from my understanding, LCDs do not blink x times a second like CRTs. So why would it cut the power to the led backlight at a high freq?
 
Yeah I've heard the whine, except it only happens when the GPU is being pegged and I can hear it coming from the GPU.
 
alphaod said:
Yeah I've heard the whine, except it only happens when the GPU is being pegged and I can hear it coming from the GPU.
Click to expand...

If not related to display brightness I think that is a different issue, although there could be a similar problem with the GPU (related to power regulation). The "brightness whine" comes from the bottom right of the screen itself.
 
I'm not sure how the display is dimmed, but PWM is how it mostly works. Noise is generated by this:

Full brightness:

<--- one pulse -->
1 |-----------------
|
0 |

Lowest brightness

<--- one pulse -->
1

0 ------------------

Half brightness:


<--- one pulse -->
1 |--------|
| |
0 --------| |

you see when you compare this to an audio wave the 'half brightness' part would generate the most noise because the difference in pulse height is biggest, it is like a perfect square wave.

You can also hear it from certain battery chargers which also work with this system, some IC's or capacitors just seem to make noise... but why not on OS-X... I've ordered a second MPB with the same specs because of this and there's the same issue again. The chance of a hardware failure problem is getting slimmer...
 
grit said:
you see when you compare this to an audio wave the 'half brightness' part would generate the most noise because the difference in pulse height is biggest, it is like a perfect square wave.

You can also hear it from certain battery chargers which also work with this system, some IC's or capacitors just seem to make noise... but why not on OS-X...
Click to expand...

Nice explanation and exactly what I have found as well. The noise gets louder right in the 5-10 backlight square range (the middle). Which is, of course, where most people use it.

As for why you don't hear it on OSX, that's a mystery. As the OP noted the noise is audible as soon as the screen turns on, even before an OS is booted. I plainly hear it in OSX and don't hear any change when running games in Parallels.

Also, the buzz/whine is only the most audible part of the noise, because it is shooting from the front of the screen towards your ears. But if I lift up the laptop and listen to the right side of the unit, like where the DVI port is, I can hear a ton of very high frequency junk being shot out. And it also stops completely when the blacklight is off. Very disappointing.
 
I have this same issue on my old mid-2006 MacBook Pro. Although, it does also happen in OS X (in fact, I don't have boot camp installed on it). No applecare for me anymore though :(.

How on earth could they still have not fixed this issue?! :(
 
no, it's not the fan, its more like you can hear the IC' switching on and off very fast to dim the screen, more or less like a dimmer works on a lightbulb. The dimmer cuts the power to the bulb at a very high frequency so you can't see it going on and off but it appears to be dimmed. To dim the light more, a bigger part of the power is cut off in this high frequency pulse. Maybe the OSX uses a different frequency for this 'Pulse Width Modulation' which is less audible, just guessing here...
Click to expand...

I agree with you here, I came to a similar conclusion. I used to experience problems just like these when displaying at refresh rates that old CRT displays didn't quite support etc. I think it is logical to conclude that this is looking like a software issue related to how the code controls the screen hardware to perform the brightness reduction. I hope apple releases a fix quickly here as it's already been a month+ since I have owned this machine and not a word...
 
I just updated to the latest bootcamp version (2.1) in Vista 32bit and it does not fix the problem. Is everyone else still experiencing the problem after updating?
 
After reading everything posted in here I have came up with what exactly is going on.

1) The high pitch noise occurs in windows xp & vista when the screen is on anything but the highest brightness.

2) It is most likely an nvidia driver issue that can be fixed I assume.

3) The potential fix on https://forums.macrumors.com/showthread.php?p=5245320#post5245320 only seems to work for windows xp users and not vista.

4) The new version of bootcamp does not fix it.

5) We have to wait for apple to get off the couch and do something about this (joy).

6) Curse my very good hearing of high frequencies...

7) Just found out my LCD screen is going bad on this new MBP. Started with one dead pixel now something has formed above it. ( Going to have to call them tomorrow....for like the 88th time)
 
Since for most people the sound occurs in OSX as well, I doubt it is a driver issue.

I also doubt a firmware fix will do anything. When has a firmware fix ever reduced a hardware-generated noise (except fans of course)?

For 1st gen 17" LED backlit screens, and likely the last implementation of the current case hardware/case design, this is likely good enough for Apple. Most people haven't noticed anything at all, and never will.

Shame that both the 15" and 17" have different audio related issues that render them anything but "Pro" machines. At least it saves me some $ though. My Macbook is cheap and silent, and Apple is no longer getting "Pro" margins out of me as a customer for the foreseeable future until they actually start making "Pro" machines again.
 
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