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MBP overheating?

O

orangezorki

macrumors 6502a
Original poster
Aug 30, 2006
633
30
Hello all,

I just thought that I would check what temperatures my 2009MBP with 2.8GHz Core2Duo was running at, and I was surprised. Both iStat Nano and Temperature Monitor report the CPU at about 70C at idle, and when I ran Prime95 for a few minutes, I saw temperatures at about 105C - I thought that the chip would scale down to avoid such temperatures! It's definitely reading in celcius, and I can feel air being pushed out the back of the machine.

So, do I have a problem, or am I getting the wrong readings?

Thanks in advance,

David
 
If it's not shutting down it's not overheating. That's it. That's all you need to know, ever. Stop looking at the temps.

How many of these threads must we have?
 
orangezorki said:
Both iStat Nano and Temperature Monitor report the CPU at about 70C at idle, and when I ran Prime95 for a few minutes, I saw temperatures at about 105C - I thought that the chip would scale down to avoid such temperatures
Click to expand...
Were they "at 105C" or "about 105C"? There's a difference, even if it's one degree. Also, temps may have to be sustained at at the max temp for more than a few seconds before shutdown occurs. 70C certainly seems high for idle temps. I suspect it's not truly idle. Launch Activity Monitor and change "My Processes" at the top to "All Processes". Then look to see what apps may be placing high demands on your CPU/GPU.

The Intel processors used in Macs are designed to automatically shut down to prevent damage if they truly overheat (around 100C/212F - 105C/221F, depending on your processor).

Unless there is a rare defect in a Mac, most temps are well within the normal operating range, considering the workload being put on them. Websites with Flash content, games and other multimedia apps will put higher demand on the CPU/GPU, generating more heat. This is normal. If you're constantly putting high demands on your system, such as gaming or other multimedia tasks, expect temps to rise and fans to spin up accordingly. It's just your Mac doing its job to maintain temps within the normal range.

Your fans are always on when your Mac is on, spinning at a minimum of 2000 rpm (for MBPs) or 1800 rpm (for MBAs, MBs and minis). They will spin faster as needed to keep temps at a safe level. If they're spinning up without increased heat, try resetting the SMC. PRAM/NVRAM has nothing to do with these issues, so resetting it will not help. Also, make sure you don't block the vents, which are located at the rear, near the hinge.

Learn about the fans in your Mac
Apple Portables: Operating temperature
 
GGJstudios said:
The Intel processors used in Macs are designed to automatically shut down to prevent damage if they truly overheat (around 100C/212F - 105C/221F, depending on your processor).

Unless there is a rare defect in a Mac, most temps are well within the normal operating range, considering the workload being put on them. Websites with Flash content, games and other multimedia apps will put higher demand on the CPU/GPU, generating more heat. This is normal. If you're constantly putting high demands on your system, such as gaming or other multimedia tasks, expect temps to rise and fans to spin up accordingly. It's just your Mac doing its job to maintain temps within the normal range.

Your fans are always on when your Mac is on, spinning at a minimum of 2000 rpm (for MBPs) or 1800 rpm (for MBAs, MBs and minis). They will spin faster as needed to keep temps at a safe level. If they're spinning up without increased heat, try resetting the SMC. PRAM/NVRAM has nothing to do with these issues, so resetting it will not help. Also, make sure you don't block the vents, which are located at the rear, near the hinge.

Learn about the fans in your Mac
Apple Portables: Operating temperature
Click to expand...

Do you have that on your desktop so you can copy and paste? I see it everywhere :rolleyes:
 
macdudesir said:
Do you have that on your desktop so you can copy and paste? I see it everywhere :rolleyes:
Click to expand...

Um since the question is asked 100 times per month, why wouldn't he have it somewhere that he can just copy and paste it? Instead of typing that out to every noob that thinks their computer is overheating.

He's trying to help people out.

How about this, try not going into every thread with the title "My Macbook is overheating", and you won't have to see it everywhere.


Have a good day.
 
GGJstudios said:
You see it everywhere because the same question is asked everywhere. :rolleyes:
Click to expand...

Ah, good point. ;)

----------
jondob said:
Um since the question is asked 100 times per month, why wouldn't he have it somewhere that he can just copy and paste it? Instead of typing that out to every noob that thinks their computer is overheating.

He's trying to help people out.

How about this, try not going into every thread with the title "My Macbook is overheating", and you won't have to see it everywhere.


Have a good day.
Click to expand...

lol i wasn't trying to insult him or complaining. I was just pointing out an observation. I go in to the threads to try to help people but GGJstudios always beats me to it :p
 
macdudesir said:
I go in to the threads to try to help people but GGJstudios always beats me to it :p
Click to expand...
I posted about an hour after the OP, and you posted about 2 hours after me. You're gonna have to pick up the pace a bit to beat an old plodder like me! :D
 
I was reading through this and look at my istats. I notices heatsink A and B, B had a number and A had a " - ". That mean its not working properly?
 
orangezorki said:
Hello all,

I just thought that I would check what temperatures my 2009MBP with 2.8GHz Core2Duo was running at, and I was surprised. Both iStat Nano and Temperature Monitor report the CPU at about 70C at idle, and when I ran Prime95 for a few minutes, I saw temperatures at about 105C - I thought that the chip would scale down to avoid such temperatures! It's definitely reading in celcius, and I can feel air being pushed out the back of the machine.

So, do I have a problem, or am I getting the wrong readings?

Thanks in advance,

David
Click to expand...

You do have a problem.

Temperatures should not be this high.
 
Nameci said:
It is but normal for the processors to be running warm, put it in a freezer and its going to be cold. Come on people, just use it.
Click to expand...

Well, 105C is right at the temperature where it's supposed to shut off:
http://ark.intel.com/products/35563/Intel-Core2-Duo-Processor-T9600-(6M-Cache-2_80-GHz-1066-MHz-FSB)

I found the following on tomshardware (forum post, so might not be 100% accurate):
~5C below Tjunction Max throttling begins (PROCTHERM), and when Tjunction Max is reached, shutdown occurs (THERMTRIP).
Click to expand...

Things seem to be a bit more complicated, e.g. the cores don't report the temperature but something called DTS, which measures the "distance" of the core temperature from Tjunction Max. Also Tjunction max varies slightly from CPU to CPU and even from core to core, its not completely surprising that no actual shutdown occurred.

The CPU reaching it's shutdown temperature, + idle temps of 70C and more (assuming it's really idle, no background processes) could actually indicate a real cooling issue. Might be worth checking the thermal paste.
 
thundersteele said:
Well, 105C is right at the temperature where it's supposed to shut off:
http://ark.intel.com/products/35563/Intel-Core2-Duo-Processor-T9600-(6M-Cache-2_80-GHz-1066-MHz-FSB)

I found the following on tomshardware (forum post, so might not be 100% accurate):


Things seem to be a bit more complicated, e.g. the cores don't report the temperature but something called DTS, which measures the "distance" of the core temperature from Tjunction Max. Also Tjunction max varies slightly from CPU to CPU and even from core to core, its not completely surprising that no actual shutdown occurred.

The CPU reaching it's shutdown temperature, + idle temps of 70C and more (assuming it's really idle, no background processes) could actually indicate a real cooling issue. Might be worth checking the thermal paste.
Click to expand...

The first thing that caught my attention, is the fact he stated it was 2009. I am assuming the OP noticed more heat than usual, over the course of its life. What I am suspecting it could be, is dirt and grime that has built up either in the intake or exhaust vents, or it could be the fans have a filth built up as well.

I would like to see the activity monitor posted, as it would provide more detail about the problem. I would agree it is annoying reading about all of these "overheating problems" but most regard the i7 cpu's with the AMD gpu's.
 
I have had this happen to me on many older MacBooks, usually after a bit over a year of ownership.

What happens is that dusts get in over time, and they either clog the fan, or they block the vents, or both. It has happened to every single MacBook I opened.

As a result, excess heat can't be exhausted as fast as they should normally, and the processor's temperature shoots up, which in turn makes the processor scale itself down to the lowest speed possible.

The true remedy is for you to open the machine up and clean it inside out. I bet you'll be surprised at how much dust you can find in there. Most of it would probably be underneath the keyboard.

The other remedy is to use Coolbook Controller to force the lowest speed and voltage possible. But that only works in Snow Leopard or below, and it doesn't solve excess heat or possible long-term damage.
 
thundersteele said:
Well, 105C is right at the temperature where it's supposed to shut off:
http://ark.intel.com/products/35563/Intel-Core2-Duo-Processor-T9600-(6M-Cache-2_80-GHz-1066-MHz-FSB)

I found the following on tomshardware (forum post, so might not be 100% accurate):
Click to expand...

Regardless of the forum post, the intel link isn't going to lie. Stress tests do tend to push a machine to its limits, but they're used to diagnose potential problems with hardware that may not consistently surface during regular use. I agree the fans may be clogged up, but getting close to temperatures that would require a forced shutdown would make me nervous too.
 
Thank you everyone for the replies,

And sorry everyone if this has been asked before, but of course it matters more when it happens to your computer!

I tried again with the torture test, and firstly noticed that there also are readings for the two cores as well as the "cpu diode", which initially reads higher than the cores. The core temps read mid 50sC when idle, just surfing etc. But when I run the torture test, they quickly ramp up to over 100, peaking at 104C. These then scale back to mid 90s, and I can hear the fan ramp up, so that hasn't failed. What I can't tell is if the CPU frequency is being throttled back.

So, may I ask these follow up questions:

1. Is there a way of telling what frequencies are currently running?

2. A couple of months back, I upgraded the RAM. Everything has been running fine since, but could I have damaged something? I did clear up a few dust bunnies, and couldn't see anything obvious that I could break, but I'm not sure.

3. I'm not adverse to building a desktop PC, in fact having just done so, and worrying about over clocking to temperatures over 80C on that, that is why I just checked the temps on the computer I use the most. But I have no serious experience with tinkering with laptops. Is there something easy I can do that might solve this problem, if it is a problem?

Thanks in advance,

David
 
About 50C idle is fine.

The torture tests are well... tests. If you don't experience any problems during normal use (i.e. shutdowns), you can probably ignore the extreme peak temperatures you get with those torture tests.

1. if you have a windows partition (bootcamped), you can install some tools that read out the CPU frequencies. I don't know if that is possible in OSX.

2. It's unlikely that you damaged something.

3. Laptop CPUs can easily take temperatures above 80C... yours is still working after all. If you want to do something, you can try to replace the thermal paste on the CPU and GPU. There's a guide somewhere on the forums, and most people who did it observed some improvements.

Have fun :)
 
As a general rule of thumb, temperatures over 95C for the CPU/GPU will result in long-term damage. While playing games, it is evident that frame rates drop as the card scales its clocks back in order to maintain temperature levels. In most OS X applications you can't notice this, but you definitely can in games. The CPU and GPU don't seem to shut down by themselves until temperatures are ludicrously high.

Take it from a PC builder/overclocker, and don't run your chips over 95 for more than five hours. I don't know what these guys are talking about with their "don't worry about it" misconceptions. And by the way, 105 is far hotter than it ever should be. Even playing Battlefield 3 or RAGE, my GPU doesn't go over 90C and my CPU 89C. This is also with an over clock of 25%.

You could try scraping off some of the thermal paste. Apple is notorious for putting far too much on. Thermal paste is meant to fill the gap between the heat sink and the CPU, but Apple puts dollops on when all that's needed is a little wipe of the stuff. When too much is applied, it actually insulates the chip from the heat sink, which leads to significantly higher temperatures.
 
w00t951 said:
Take it from a PC builder/overclocker, and don't run your chips over 95 for more than five hours. I don't know what these guys are talking about with their "don't worry about it" misconceptions. And by the way, 105 is far hotter than it ever should be. Even playing Battlefield 3 or RAGE, my GPU doesn't go over 90C and my CPU 89C. This is also with an over clock of 25%.
Click to expand...

Which CPU are you using? Some of the C2D have Tjunction max of 105 C, while the newer quad cores are down to 100 C. Throttling apparently starts 5C below, at 100 C and 95 C respectively.

I don't know where you pull your numbers from. 94 C is fine, but 96 C is bad?
 
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I'm using the 2.8 core2duo, the last version before they started using the core I processors.

Have backed up everything, so later on will delve into the bootcamp partition to see if the temps are really that high and if the clock speed is scaling down.

Thanks again,

David
 
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