Also get hair drying speed bursts, but not random.
Hi, first, let me specify the machine and environment.
Leopard 10.5 server
Mac Mini 1.83Ghz C2D model
Upgraded to 3Gb RAM.
smcfancontrol
Temperature Monitor 4.2
I'm using the machine in a cool room (about 15 degrees right now).
Idle temperature is:
HDD 35
AMB 36
CPUA HS 35
CPU C1 38
CPU C2 40
CPUA TD 40
NB P1 40
NB P2 40
Fan Speed ~1500 (minimum allowed).
This is perfectly reasonable at idling, I believe.
With CPU duty cycle of about 10% generated by server tasks (including short peak demands), the fan tends to increase to about 2500 for short periods and is not really a problem.
However, I've located specific stimuli which trigger the ridiculously increased fan activity.
It does not appear to be directly CPU related, but rather certain GPU related activities which cause the problem.
For example, I open any *long* page in Safari, scroll to the bottom and back to the top using the right hand handle. I do this ten times and my fan is running at over 4000 rpm!
Artificially scrolling is one thing, but even when I use the scroll ball of an Apple mouse to scroll slowly through a page and the fan rams up to hairdrier mode.
This is the most annoying thing, rendering it almost unusable for me since I really like to use this for surfing and the noise is up and down like a yoyo every time I scroll 8one tends to do that a lot when surfing).
As soon as I stop, it starts returning to normal at about 100 rpm per second, so after about 30 seconds it's back down to around 2000.
Spectrum screen saver for example pushes the fan imediately to 5500 in 15 seconds, but all temperatures is quite stable.
Yet no temperatures ever went above 50!
In fact, stop the activity and the continued fan activity pushed my whole computer down to about 10 degrees below idling temp!!!!
I'm now running Rember with the screensaver on, both cores are pegged at 100%
my HDD is going down from 40 to about 25 degrees!
CPU A Heatsink is at 34, CPU cores are at 47 and 49 and appear stable!!! NB1 and 2 are at 40 and 39.
My fan is now running at 4200 and is quite annoying.
Now, I cut out the screen saver, reducing CPU usage to one thread yet the fan has not slowed. (CPU coores temp dropped about 45 and 48 degrees - CPU HS NB1 and NB2 are now at 34/35 and 36 respectively).
At first, I assumed it was my RAM swap, having forgotten the little HDD sensor, but the fan is not pegged all of the time so I don't think it's that.
It suffices to say that this is not an overheating problem...
I think, first, I'll check for any small sensors unplugged by the swap.
Then I should replace the RAM with original 512x2
If this does not work, I'll backup 10.5 Server and put 10.5 Client back on and see what happens.
Any ideas?
Cheers.