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To Everyone with Random Shutdowns! (Solved! REALLY!)

Hey all,


I had posted about a week back about my Macbook (Core duo white, late 2006), it was having the same symptoms as some of the others with the known random shutdown syndrome (RSS). Like many others I had thought it was the end of my macbook and the logicboard needed replacing because that is what the 'genius' people do, but I was still wondering what would cause it. It would randomly shut off! (or so I thought) I'd be typing in Safari, watching a youtube video, and even playing games, it would just shut off and I could hear the hard drive spin down. I'd restart and it would do it again sometimes right away, sometimes hours later.


This got me to thinking (like others have said) that it must be an issue with over heating. To test my theory I backed up my HD, and tried to reinstall Snow Leopard after zeroing the HD (as a fresh install). During the install process the Macbook's fan started to get loud and then it happened, it died again! So, this proved to me that it is NOT a software/OS issue at all, which means the said efforts in other posts of changing screen saver and energy saver settings had nothing to do with the cause! Aha moment!


I thought to myself... something is making it shutdown, obviously, and has to do with too much heat as the fan was going crazy even while reinstalling the OS. After reading many posts on different support forums I came accross the possibility that it could be the heatsink and/or sensor that is attached to it. I also found out that this "RSS" only applies to the non-unibody, core duo, and core 2 duo macbooks... you know what that means?


These models are the only ones with the shared memory and GPU on the same heatsink! GAH! A possible solution presents itself? To make a long post even longer... I removed the keyboard, carefully unscrewed the heatsink and fan and what did I see? Cracked and dried out thermal paste on the CPU AND GPU, they are both under the same heatsink after all, this was bad, really bad.


Luckily I had some Arctic Silver thermal paste in a tube from years ago when I upgraded my PowerMac CPU. Using some rubbing alcohol and a soft cloth I removed the crud on the heatsink, processor, and GPU (I might add that there was way too much paste on there in the first place). I waited an extra few minutes to make sure the alcohol evaporated, and then I applied a small (dime sized) amount of thermal past directly onto the two chips, I aligned the heatsink carefully and gave it a very small gentle push down onto the chips, reattached the sensor wire to the mainboard, and screwed the heatsink back in.


After putting the keyboard back on and making sure all screws were in... I immediately turned on the laptop and reinstalled the OS. The OS install took approximately 10 mintues! (crazy!) The last time I did that it took over 30 mins to install! I was stunned!


After the OS installed I let the computer idle and shut down, I let it sit for about an hour to allow the paste to contract as it cooled. After starting up again I immediately downloaded Temperature Monitor and installed it (I did have it running when my mac had RSS by the way), here are the results to prove my theory:


My Macbook with RSS:

CPU1 and CPU2 Idle temp - 114 degrees (F)

Heatsink temp - 128 degrees (F)

Approximate over heating temp - 184 degrees (F) (causing the heatsink sensor to shutdown the laptop)


My Macbook with new high quality thermal paste:

Idle temp of CPU1, CPU2, and GPU - 77 degrees (F)

Heatsink temp - 84 degrees (F)

Running temp with adobe CS4, youtube, and typing this message - 103 degrees (F)


Pretty amazing if you ask me!


Before I applied the thermal paste my Macbook took at least a minute to start up with a fresh OS install, now it only takes about 15 seconds! I have not heard the fan spin up and go crazy since! And I can't even explain to you how much fast it is now!


This does prove that Random shutdown syndrome (RSS) is caused ONLY by your GPU over heating due to old thermal paste between the chips and heatsink! A design flaw by Apple? probably not because thermal paste will crack and dry over time.


This also proves that energy conversion to data in the chips can decrease because of over heating, causing the computer performance to dramatically drop!


So before you take your out-of-warranty macbook to Apple or a repair shop, see what your internal temp readings are and try to replicate the problem with over heating your CPU/GPU! This was a 10 minute fix! I am still amazed at how much faster everything is, and haven't had a random shutdown since! I hope this helps alot of people that think they are out of luck and have to pay to get it fixed!


- Cory -

MacBook, Mac OS X (10.6.8)

Posted on Feb 16, 2012 10:55 AM

Reply
1 reply

Feb 22, 2012 4:43 PM in response to Cory Schaal

I too have this problem as well and it has been getting worse lately, I don't know what to do anymore. Here is a little info about my macbookPro. I have the late 2008 unibody model, i bought it in late 2009 Refurbished from Apple. Recently my mac has been turning off out of nowhere. I may be doing something and all of a sudden it just shuts off, it usually happens faster when i start to open up more programs like Photoshop or Final Cut Pro. My mac is out of warranty now and i dont know how much apple is going to charge me to fix it. i mean they want 50 bucks just to talk to them on the phone (ridiculous if you ask me)!.


I have a temperature sensor installed and here is my data


CPU A Proximity: 126F

CPU A Temperature Diode: 133F

Graphics Processor Chip 1: 122F

Graphics Processor Heatsink 1: 113F

Graphics Processor Heatsink 2: 126F

Graphics Processor Temperature Diode: 131F

Left Palm Rest: 91F

Main Heatsink 3: 122F

Main Logic Board: 118F

Northbridge Chip: 127F

Northbridge Position: 124F


Here is more data from the Power


Battery Information:


Model Information:

Manufacturer: GSA-1281

Device Name: ASMB016

Pack Lot Code: 0

PCB Lot Code: 0

Firmware Version: 0

Hardware Revision: 0

Cell Revision: 0

Charge Information:

Charge Remaining (mAh): 3739

Fully Charged: No

Charging: No

Full Charge Capacity (mAh): 4610

Health Information:

Cycle Count: 68

Condition: Normal

Battery Installed: Yes

Amperage (mA): -1766

Voltage (mV): 11793


System Power Settings:


AC Power:

System Sleep Timer (Minutes): 0

Disk Sleep Timer (Minutes): 0

Display Sleep Timer (Minutes): 90

Automatic Restart on Power Loss: No

Wake on AC Change: No

Wake on Clamshell Open: Yes

Wake on LAN: No

Display Sleep Uses Dim: Yes

GPUSwitch: 2

PrioritizeNetworkReachabilityOverSleep: 0

RestartAfterKernelPanic: 157680000

Battery Power:

System Sleep Timer (Minutes): 60

Disk Sleep Timer (Minutes): 0

Display Sleep Timer (Minutes): 2

Wake on AC Change: No

Wake on Clamshell Open: Yes

Current Power Source: Yes

Display Sleep Uses Dim: Yes

GPUSwitch: 2

Reduce Brightness: Yes

RestartAfterKernelPanic: 157680000


Hardware Configuration:


UPS Installed: No


AC Charger Information:


Connected: No

Charging: No


PLEASE HELP ME, I CAN NO LONGER TRUST MY MAC FOR WORK. any replies will be appreciated. thanks

To Everyone with Random Shutdowns! (Solved! REALLY!)

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