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Apple has released MacBook SMC Firmware Update 1.1, which aims to improve the MacBook's internal monitoring system and address issues with unexpected shutdowns.

A number of MacBook owners have had their MacBooks intermittently randomly shut down on them, an issue which has come to be known as MacBook RSS (Random Shutdown Syndrome). In a recent summary of the issue, including a pending class-action lawsuit, AppleInsider quotes Ogrady's PowerPage that nails down the root cause of the issue to the following:

"Essentially the heatsink can expand during use, and comes into contact with the lead from the [thermometer's] sensor cable," reads a more detailed explanation posted at Ogrady's Power Page. "A short circuit results, and the SMC (System Management Controller) pulls the plug. Once the system cools down, the heatsink [recedes] and the contact is broken."

As is the case with all firmware upgrades, Apple cautions users to not interrupt the update. Detailed information regarding the update can be found here.
 

longofest

Editor emeritus
Jul 10, 2003
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some speculation...

here's some of my speculation about this update...

While we don't know exactly how the Firmware update was designed, it would appear as though the update could simply ignore symptoms of a SMC short circuit to allow the laptop to continue operating. If this is the case it may degrade a MacBook's ability to detect true over-heat situations.

AppleInsider had previously reported that a new MacBook logic board was under development to eliminate the root hardware issue, but a release date was not known.
 
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gavd

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Jan 30, 2006
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A friend of mine has just received his MacBook back from Apple where they replaced the heatsink because of the issue. Hopefully this will solve it for others though!
 
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QCassidy352

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Mar 20, 2003
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longofest said:
While we don't know exactly how the Firmware update was designed, it would appear as though the update will simply ignore symptoms of a SMC short circuit to allow the laptop to continue operating. If this is the case it may degrade a MacBook's ability to detect true over-heat situations.

I agree. This seems a risky way to deal with a hardware defect. My first macbook had RSS, and apple exchanged it for a new one with me. If this one started doing it I'd be very worried - firmware update or no.
 
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Donz0r

macrumors 6502a
Jun 29, 2006
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Just got my macbook back today.

They replaced the heatsink (Again), apparently last time they just replaced it with another faulty one because I complained about it taking too long (over 2 weeks) even though they had already come out with another heatsink. This time they replaced it with a better heatsink. So hopefully it hsouldn't happen again. If it's a hardware issue though, I don't see how a firmware update would fix anything.
 
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runninmac

macrumors 65816
Jan 20, 2005
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Rockford MI
Oh dang, these firmware updates make me nervous... so im going to wait and let others be the guinea pig.

PS: This should save apple a ton of cash
 
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kainjow

Moderator emeritus
Jun 15, 2000
7,958
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After applying the update, it seems like it's running cooler. I'm getting 53-54C now, when normally it's 58-59.
 
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iViking

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Oct 23, 2006
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Not too inspiring for those of us who know how serious RSD is.

If it works, great...but there will always be a question as to how fragile the inner workings of a RSD computer is.

I like Apple but I was surprised in a bad way about this...imagine your computer shutting down completely and completely randomly every 5-120 minutes.

I got a replacement and I'm sure most others will want one, too.
 
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brepublican

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Jul 22, 2005
812
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NY
:mad: It's about time Apple did something about these MB's. I work for IT and I've had atleast 5 reports of random shutting down (and then failing to go past the gray screen after start up). EDIT: the past fortnight

I wouldn't go near these machines if I was in the market for a portable...
 
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longofest

Editor emeritus
Jul 10, 2003
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QCassidy352 said:
I agree. This seems a risky way to deal with a hardware defect. My first macbook had RSS, and apple exchanged it for a new one with me. If this one started doing it I'd be very worried - firmware update or no.

Yup. The way to properly handle the problem is to replace the MoBo's. I don't want to start a "this update will make your laptop overheat" rumor, but I'm pretty certain that they are trying to bypass the root defect.
 
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kainjow

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Jun 15, 2000
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brepublican said:
I wouldn't go near these machines if I was in the market for a portable...
Well my MB was bought the day they were announced - my local Apple store didn't have them on display yet :) and mine hasn't had the shutdown issue.

I thought this pic Engadget posted is pretty funny:
macbook-shutdown-fix.jpg
 
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slb

macrumors 6502
Apr 15, 2005
403
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New Mexico
longofest said:
While we don't know exactly how the Firmware update was designed, it would appear as though the update will simply ignore symptoms of a SMC short circuit to allow the laptop to continue operating. If this is the case it may degrade a MacBook's ability to detect true over-heat situations.

This is what I assumed when I read that the update "resolves" the issue, which is pretty optimistic wording. Perhaps they implemented some firmware method to detect overheating that doesn't rely on the sensor. I would love to know more information, since this update will appear for everyone with a MacBook whether or not they've been experiencing the shutdowns.
 
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LSK6453

macrumors member
Aug 16, 2006
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0
I applied the firmware w/o issue... Looks to be running well and my temps are staying more even as I continue to use it.

43.2 C right now
 
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MacinDoc

macrumors 68020
Mar 22, 2004
2,266
5
The Great White North
longofest said:
here's some of my speculation about this update...

While we don't know exactly how the Firmware update was designed, it would appear as though the update will simply ignore symptoms of a SMC short circuit to allow the laptop to continue operating. If this is the case it may degrade a MacBook's ability to detect true over-heat situations.

AppleInsider had previously reported that a new MacBook logic board was under development to eliminate the root hardware issue, but a release date was not known.
Perhaps it allows the MacBook to recognize the output you would get from a short-circuited thermometer cable and ignore it, while still monitoring its regular output (at least when it's not short-circuited). Or maybe it decreases the threshold at which the fans kick it, preventing the heat sink from expanding as much. I doubt that Apple would provide a firmware update that would instruct the MacBook to ignore all information from the thermometer, as this would be a recipe for disaster in no time.
 
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081440

macrumors regular
Mar 14, 2006
160
24
New Jersey
How can one tell if their MacBook is one that could be affected?


And


How are you guys finding your temperatures? A dashboard widget or something?
 
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chairguru22

macrumors 6502a
May 31, 2006
638
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PA
081440 said:
How can one tell if their MacBook is one that could be affected?


And


How are you guys finding your temperatures? A dashboard widget or something?

iStat nano widget
 
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Gfog

macrumors member
May 16, 2006
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0
Ive held off the last firmware update (ver 1.0) as i dont want the fans on contineously, does this update still lead to the fans being on more?
 
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MacinDoc

macrumors 68020
Mar 22, 2004
2,266
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The Great White North
kainjow said:
After applying the update, it seems like it's running cooler. I'm getting 53-54C now, when normally it's 58-59.
LSK6453 said:
I applied the firmware w/o issue... Looks to be running well and my temps are staying more even as I continue to use it.

43.2 C right now
So, it looks like Apple is trying to fix the problem by keeping the MacBook cooler, thus preventing the heat sink from expanding enough to come into contact with the cable. A simple, elegant solution, except it will likely cause increased fan use and decreased battery life, but these are minor inconveniences compared to random shutdown.
 
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slb

macrumors 6502
Apr 15, 2005
403
90
New Mexico
MacinDoc said:
So, it looks like Apple is trying to fix the problem by keeping the MacBook cooler, thus preventing the heat sink from expanding enough to come into contact with the cable. A simple, elegant solution, except it will likely cause increased fan use and decreased battery life, but these are minor inconveniences compared to random shutdown.

I don't think this is what is happening, because Apple has increased fan frequency before, and it didn't prevent the issue. The KB page claims that this update "resolves the issue," which is pretty definitive wording, so I suspect the firmware's sensor monitoring behavior has changed in some way that ignores the short-circuit. I'd love to have more information from those technically-minded enough to find out.
 
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nsjoker

macrumors regular
Apr 13, 2005
154
0
Miami, Fl
kainjow said:
Well my MB was bought the day they were announced - my local Apple store didn't have them on display yet :) and mine hasn't had the shutdown issue.

I thought this pic Engadget posted is pretty funny:
macbook-shutdown-fix.jpg

i am laughing uncontrollably right now, wowowowowow :D :D :D :D :D :D
 
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