Massive Overheat Issue Help!?

[Traverse]

Hi,

I have a 2011 15" MacBook Pro and I'm fairly knowledgeable with it. Something just happened that really freaked me out and I hope some of the veterans here can help..

I was watching an HD movie in iTunes, thats it, when I heard my fans speed up. I check and they were 3200 rpm a piece and I ignored that because HD playback uses CPU power. (I check Activity monitor and iTunes was using about 15% CPU).

Well, about 20 minutes later the fans grew very distracting and I checked and they were running at 6200 rpm a piece! I quickly opened Activity monitor AND opened a live view of CPU I attached the screen shot (and note that this was a low point of usage) iTunes was still using the normal amount (23% and then back down), but I quit it anyway. The screenshot is after iTunes was quit. I waited about 30 seconds and noticed that the CPU was running full force maxing 4+ virtual core. What scares me is that I opened Activity Monitor and ordered it by CPU usage and the max CPU usage going on was 1.4% by activity monitor itself. I waited and watched and nothing else was using over 1%, but the live CPU graph was still maxed and the fans were still at 6200 rpm. I restarted my Mac to get things back to normal.

Any ideas!? Should I expect it to burst into flames...

 

[dastinger]

Your CPU will never ever burst into flames due to heat simply because the MBP will turn itself off in case it reaches the maximum temperature defined by Intel for the CPU.

In my case (2012 rMBP) the max temperature is 105°C. If it reaches that, the MBP shuts down for safety reasons.

Did this happen once or is it consistently happening? Can you recreate it?

 

[GGJstudios]

If you're not already doing so, use iStat Pro (free) or iStat Menus ($16) to get accurate readings of your temps, fan speeds, etc., rather than relying on your sense of touch or sound. A forum member has posted a copy of iStat Pro that has been "tweaked" to enhance compatibility with Mountain Lion. You can download it here.

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The Intel processors used in Macs are designed to automatically shut down to prevent damage if they truly overheat. CPU Tjmax = 105C (221F), GPU Tjmax = 100C (212F) on i3, i5, i7 processors. (Source: Intel)

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Unless there is a rare defect in a Mac, most temps are well within the normal operating range, considering the workload being put on it. 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.

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It is also quite normal for your Mac to become extremely hot to the touch during intensive operations. The aluminum body transfers heat more effectively than other materials used in computer casings, so you will feel the heat more. This doesn't indicate that it's overheating and will not harm the computer to be hot to the touch.

The bottom of your Mac notebook may become very warm during normal use. If your notebook is on your lap and gets uncomfortably warm, move it to a stable work surface that allows for good ventilation.

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), or 1200 for the newest MBAs. Older iMacs have 3 fans with minimum speeds in the 800-1200 range, while the newest iMacs have a single fan, spinning at a minimum of about 1400 rpm. They will spin faster as needed to keep temps at a safe level. If your fans are spinning up without increased heat, try resetting the SMC. (PRAM/NVRAM has nothing to do with these issues, so resetting it will not help.)

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The intake and exhaust vents are in the back of the computer near the hinge on all Mac notebooks (except the new MBP with retina display, which has intake vents along the sides at the bottom). The iMac vent is a slot on the back near the top of the computer. Make sure the vents remain unblocked to allow your computer to perform at its best.

Learn about the fans in your Mac

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Mac Portables: Operating temperature​

For Flash-related issues:

• Find your Flash version and make sure it's the latest version available.
• Install ClickToFlash (Safari), Flashblock (Firefox) or FlashBlock (Chrome) to control which Flash content plays on websites.
• Use the YouTube HTML5 Video Player to watch YouTube videos, when available. (May impact fullscreen viewing. See link for details.)

 

[Traverse]

Your CPU will never ever burst into flames due to heat simply because the MBP will turn itself off in case it reaches the maximum temperature defined by Intel for the CPU.

In my case (2012 rMBP) the max temperature is 105°C. If it reaches that, the MBP shuts down for safety reasons.

Did this happen once or is it consistently happening? Can you recreate it?

Sorry, the flame thing was poorly conveyed sarcasm. No, this has only happened once and I tested it for an hour and it has not occurred again, it was just weird that I couldn't find a cause.

If you're not already doing so, use iStat Pro (free) or iStat Menus ($16) to get accurate readings of your temps, fan speeds, etc., rather than relying on your sense of touch or sound.

Thank you for the info, I due use the above mentioned programs and I do know
about the minimum 2000 ish rpm while operation. I appreciate you taking the time to type all that out, I didn't know about the Intel stats.

It was just bothering me that something was pushing the CPU to such high levels and I couldn't find it...

 

[jav6454]

No, CPUs don't burst into flames, at most you'll get thermal throttling (in other words, system slow down) until your CPU cools down.

HD can go hard on a CPU on rare occasions, it has happened to me.

 

[Traverse]

By the way, GGJstudios,

I've seen several other of your posts, how do you know all this stuff You must really do your research.

And, out of curiosity, what is a "macrumors Westmere" I've never seen that title anywhere else...

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No, CPUs don't burst into flames, at most you'll get thermal throttling (in other words, system slow down) until your CPU cools down.

HD can go hard on a CPU on rare occasions, it has happened to me.

The flame thing was sarcasm, but I knew HD used CPU, but I didn't know just how hard. Thanks for the warning, Ill keep it in mind.

 

[jav6454]

By the way, GGJstudios,

I've seen several other of your posts, how do you know all this stuff You must really do your research.

And, out of curiosity, what is a "macrumors Westmere" I've never seen that title anywhere else...

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The flame thing was sarcasm, but I knew HD used CPU, but I didn't know just how hard. Thanks for the warning, Ill keep it in mind.

He just copies and pastes pre-written responses. Sometimes he does it without fully reading or comprehending what is going on.

As per "macrumors Westmere" it is just a user title based on post count. Higher post count, the higher and more recent the CPU codename next to the word "macrumors" is.

No problem for the heads up.

 

[Traverse]

Well, I appreciate everyone's help. This has been an awesome site for tips and help.

 

[GGJstudios]

By the way, GGJstudios,

I've seen several other of your posts, how do you know all this stuff You must really do your research.

I have done a lot of research over the years, and have composed standard responses to frequently-asked questions. Those responses are updated as information changes. This is far more efficient when answering tens of thousands of questions over the years, to make sure important information isn't left out and to make sure answers are consistent. While my posts don't always apply to every situation, they're usually on-target and useful. And yes, I do make mistakes from time to time.

And, out of curiosity, what is a "macrumors Westmere" I've never seen that title anywhere else...

It's a forum-assigned user title, based on post count. From the Forum FAQ: How do user titles work?