Computer fan doesn't stop

[refugeeman]

I have a Mac Pro Dual-Core Intel Xeon running Snow Leopard. The fan now comes on and is loud and continuous. I've tried re-starting and shutting down overnight but it won't cut off. Never had this problem before and I usually don't shut down my computer. Has anyone had this problem or any ideas how to fix this problem.

 

[simsaladimbamba]

Have you tried an SMC reset yet?
Intel-based Macs: Resetting the System Management Controller (SMC)

 

[Gav2k]

Wirelessly posted (Mozilla/5.0 (iPhone; CPU iPhone OS 5_0 like Mac OS X) AppleWebKit/534.46 (KHTML, like Gecko) Version/5.1 Mobile/9A334 Safari/7534.48.3)

Also have u cleaned the heatsink's at all??

 

[refugeeman]

simsaladimbamba success

simsaladimbamba,
I just tried resetting the SMC and BINGO! it worked right away.
Many thanks for your suggestion.

 

[pbanas]

Gotta love MacRumors helpers

SMC reset worked like a charm. I'd been listening to the fan for a month and turning the music higher and higher!

 

[pbanas]

Solution worked for 20 minutes - back to fan!

Alas. What now?

 

[GGJstudios]

Alas. What now?

Launch Activity Monitor and change "My Processes" at the top to "All Processes", then click on the CPU column heading once or twice, so the arrow points downward (highest values on top). Also, click on the System Memory tab at the bottom. Then take a screen shot, scroll down to see the rest of the list, take another screen shot and post them.

 

[atlanticza]

Mac Pro fans run continuously.

I have a similar problem... even from a stone cold start. Fans start on grey screen startup. Reset SMC, PRAM etc. All updates up to date. No unusual activity in Activity Monitor. Any help much appreciated!

 

[GGJstudios]

I have a similar problem... even from a stone cold start. Fans start on grey screen startup. Reset SMC, PRAM etc. All updates up to date. No unusual activity in Activity Monitor. Any help much appreciated!

Install iStat Pro to get accurate readings of your temps and fan speeds. Then follow the instructions in my last post, including posting a shot of iStat Pro.

 

[atlanticza]

Here you go...

Thanks for the help

 

[GGJstudios]

Thanks for the help

I don't recall what minimum speeds are for the Mac Pro, but your fan speeds don't appear to be extremely high. There's nothing in Activity Monitor that points to any high demands on your system, but your temps look a bit off to me. I'd try resetting the SMC again. NVRAM/PRAM has nothing to do with these issues, so resetting that won't help.

 

[wonderspark]

My Mac Pro is basically at idle at the moment, with fan sensors reading:
Booster Fan CPU A: 798
Exhaust Fan: 510
Fan Expansion Slots: 1511
Intake Fan: 510
Power Supply Fan: 940

I also have the Fan Control app running, with fan speeds cranked down to the minimums until temps breach 111 degrees F. Hope that helps.

 

[atlanticza]

I tried that a number of times but to no avail. Thanks for your interest!