So, I'm noticing really high idle CPU temps (70c) on my first generation (Late 2012) rMBP. Pretty sure these cannot be normal. AppleCare has expired, so is it worth tearing it down, cleaning the fans and reapplying thermal paste? Thanks in advance for your help! S
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Late 2012 rMBP - High idle temps
- Thread starter sammy2066
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You don't even to open the computer unless you want to be really thorough. A can of compressed air should do the trick and a very basic cleaning could be as simple as just blowing into the air vent at the back. However be warned that you may end up ingesting some dust by doing that.
Already tried that, no change in temps - think a teardown and reapplication of thermal paste should do the trick.
I'm not sure if that's going to help all that much as the thermal paste only lowers the temperatures by a few degrees over no thermal paste even under sustained full stress. Remember seeing some Australian guy try a bunch of food items as thermal paste and found that things like mayonnaise, tomato sauce, vegemite and toothpaste only increase temperatures by 2-5 degrees over proper thermal paste.
Before you start taking your machine I'd recommend having a look at what activity monitor has to say about what's running when the machine is supposedly "idle". These high idle temperature issues used to quite often be just some driver for a printer or some peripheral that's crashed or otherwise not working as it should stressing the CPU when the machine is supposed to be at idle.
Damn the Metric system! (158F for us that are still stuck on the antiquated system that makes no logical sense whatsoever)
Is it a 15 or a 13?
I'm guessing you already did this, but what percent is your CPU when it is at this temp? 1-3%?
I'm also guessing you have already reset the PRAM/SMC, tried booting to safemode, and attempted reinstalling the OS
Is it a 15 or a 13?
I'm guessing you already did this, but what percent is your CPU when it is at this temp? 1-3%?
I'm also guessing you have already reset the PRAM/SMC, tried booting to safemode, and attempted reinstalling the OS
I had very high "idle" temps on my 2012 rMBP as well, around 70 degrees C, until I discovered that Bit Defender was running one core at 100% almost non-stop. Had to uninstall and reinstall the program and the problem went away. Check your CPU usage before you go messing around trying to clean the fans and things.
That's great advice, actually...though it NEVER hurts to blow compressed air through a machine, no matter HOW clean it is
Sorry for the late reply, and thank you for all the great advice - see below. 
Yep, already checked that - no rogue processes hogging idle CPU cycles.
Agreed. This morning however, I simply opened the case (had to wait a week for damn Torx 1.2 (P5) bit to arrive). Cleaned the fans and vents with compressed air, and idle temps have dropped by a whopping 20c to 60c and light usage temps dropped by almost 10c to 70c. I also installed smcFanControl and increased both fans to 3000rpm, which has also helped. Going to monitor temps over the next few days before breaking out the thermal paste - I prefer Arctic Ceramique since its non-conductive. I learnt this the hard way when I fried my 9800XT back in 2002 with AS5 - that wasn't my finest hour. :/
Right, so I'd done that already (see above) - I only use this machine for light browsing, MS Office, and media consumption - no AV software installed, running 10.12.4 beta and not much else.
Yes, I love compressed air - it's awesome! (y)
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I still say 60c idle is high, but load temps are what really matters.
As for AS5, just have to remember a dip in the center the size of a large grain of rice. Not that the Ceramique is bad, but my understanding is that it can "glue" the CPU to the heat sync. . .though admittedly I've never used it.
If it makes you feel any better, I've seen worse. About 6 or so years ago I tore down one of my parents ancient computers after it had failed and been replaced. . and found ALUMINUM FOIL covering the heat sync! Someone forgot to take off the protective coating before mounting it! HP at it's finest
As for AS5, just have to remember a dip in the center the size of a large grain of rice. Not that the Ceramique is bad, but my understanding is that it can "glue" the CPU to the heat sync. . .though admittedly I've never used it.
If it makes you feel any better, I've seen worse. About 6 or so years ago I tore down one of my parents ancient computers after it had failed and been replaced. . and found ALUMINUM FOIL covering the heat sync! Someone forgot to take off the protective coating before mounting it! HP at it's finest