CPU and HD fans at 0 while running

jeeplj8

macrumors member
Original poster
Jan 4, 2014
48
3
I thought after some upgrades my MacPro sounded awful quiet...

iStat shows the CPU and the HD/Expansion fans at 0 RPM. Admittedly, temps overall look very stable and normal, but shouldn't the fans be spinning a little?

actually memory seems a little hot:
CPU temps range from 21-31
Memory 61-72
 
Last edited:

paulrbeers

macrumors 68040
Dec 17, 2009
3,960
120
I thought after some upgrades my MacPro sounded awful quiet...

iStat shows the CPU and the HD/Expansion fans at 0 RPM. Admittedly, temps overall look very stable and normal, but shouldn't the fans be spinning a little?

actually memory seems a little hot:
CPU temps range from 21-31
Memory 61-72
The fans are running just not registering. Your mac would overheat in a second if the fans weren't running. Temps look fairly normal.
 

DeltaMac

macrumors G3
Jul 30, 2003
9,894
2,522
Delaware
Those fans (CPU and HD) would be the large fans, immediately behind the front panel. You can easily check to see if those fans start turning when you turn on the the computer (shut down completely, then notice the fans are not turning, and watch the fans while you press the power button), or you should be able to see from the front that the fans are turning - they will ALWAYS be running when power is on.
 

jeeplj8

macrumors member
Original poster
Jan 4, 2014
48
3
Those fans (CPU and HD) would be the large fans, immediately behind the front panel. You can easily check to see if those fans start turning when you turn on the the computer (shut down completely, then notice the fans are not turning, and watch the fans while you press the power button), or you should be able to see from the front that the fans are turning - they will ALWAYS be running when power is on.
they are running, slowly, but istat shows 0 rpm. is there something I could have knocked loose when I removed them to get tot the SATA connectors?

Thanks for the info
 

DeltaMac

macrumors G3
Jul 30, 2003
9,894
2,522
Delaware
they are running, slowly, but istat shows 0 rpm. is there something I could have knocked loose when I removed them to get tot the SATA connectors?...
Yes, you could have left a connector loose - however, if that happened, the fans wouldn't be running at all. You can always use one of the fan control apps to force the fans to a higher speed, just as a test. If you CAN'T control the fan speed, then that would be a different issue, too.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.