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My fans are going crazy..
- Thread starter mfaye21
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Open Applications / Utilities / Activity Monitor and select to SHOW ALL PROCESS and sort by CPU use.
Then report back if any process is hogging up the CPU.
Btw, what is the temperature of the CPU (in Celsius and Fahrenheit)? What application does say that your fans are running at those speeds?
Then report back if any process is hogging up the CPU.
Btw, what is the temperature of the CPU (in Celsius and Fahrenheit)? What application does say that your fans are running at those speeds?
Things to check
- reboot & don't start any programs - fans still fast?
- in Activity Monitor, when you have no programs open the CPU should be mostly idle (about 90% idle), if not you have a rogue process (eg Flash)
- download iStat Pro and check your temperatures. At idle CPU should be 40-60 C (depends a bit on what model CPU/MBP you have). All other temps should be lower.
- run Hardware Test on your install DVD. Sometimes a faulty sensor can cause the Mac to go into "failsafe" mode where it runs the fans full speed. HW test would show a failed sensor. Sensors are pretty easy & cheap to replace though!
- reboot & don't start any programs - fans still fast?
- in Activity Monitor, when you have no programs open the CPU should be mostly idle (about 90% idle), if not you have a rogue process (eg Flash)
- download iStat Pro and check your temperatures. At idle CPU should be 40-60 C (depends a bit on what model CPU/MBP you have). All other temps should be lower.
- run Hardware Test on your install DVD. Sometimes a faulty sensor can cause the Mac to go into "failsafe" mode where it runs the fans full speed. HW test would show a failed sensor. Sensors are pretty easy & cheap to replace though!
Again: How hot is the CPU?
And have you selected to SHOW ALL PROCESSES in Activity Monitor?
And have you taken the steps Pax recommended?
where are you? now is summer time in many areas of the world, so higher temps might be surrounding your mbp. what is your room temp?
This probably doesn't help the OP, but thanks for the heads up about selecting "All Processes" in Activity Monitor. Some background process in TechToolPro was hogging the CPU (showed 100%). I deleted it, and within minutes, the fans had spun down from nearly 4000 rpm to around 2000, and the temp dropped from about 80 C, to 62-64! So glad to have solved that problem!
@OP
Ignoring the CPU, your internal temperatures all seem quite high:-
Your enclosure base is 35-36 C, much hotter than mine at 28 C
Your Northbridge is very hot at 53C compared to mine at 35 C
Your HDD is at 38 C vs mine at 30 C
Your heatsink is also hot (mine at 43 C)
I suspect something is blocking the fan vent. Even though your CPU is definitely idle or near-idle the internal temps across the whole computer are quite high. Most of the heat seems to be soaking into the computer internals. This is not the way it is supposed to work. The only hot part inside the MBP should be the CPU and heatsink, then the fan should suck the heat straight from the heatsink.
I think Apple sets the fan algorithm to try to keep the CPU, the Northbridge, the enclosure and the HDD cool. Each has a threshold temperature. If any of them go over threshold the fan speeds up.
I suspect the fan is working hard to try to keep the enclosure or HDD cool, not the CPU.
I would talk to Apple, I think you may have a minor problem. If you are electronics-wise and out of warranty you might want to take it apart and look at the airflow path.
Ignoring the CPU, your internal temperatures all seem quite high:-
Your enclosure base is 35-36 C, much hotter than mine at 28 C
Your Northbridge is very hot at 53C compared to mine at 35 C
Your HDD is at 38 C vs mine at 30 C
Your heatsink is also hot (mine at 43 C)
I suspect something is blocking the fan vent. Even though your CPU is definitely idle or near-idle the internal temps across the whole computer are quite high. Most of the heat seems to be soaking into the computer internals. This is not the way it is supposed to work. The only hot part inside the MBP should be the CPU and heatsink, then the fan should suck the heat straight from the heatsink.
I think Apple sets the fan algorithm to try to keep the CPU, the Northbridge, the enclosure and the HDD cool. Each has a threshold temperature. If any of them go over threshold the fan speeds up.
I suspect the fan is working hard to try to keep the enclosure or HDD cool, not the CPU.
I would talk to Apple, I think you may have a minor problem. If you are electronics-wise and out of warranty you might want to take it apart and look at the airflow path.