E6400, fan constantly on

After booting up and logging in, for about 30 seconds my computer is quiet, and then the fan kicks in and doesn't quit. The temps are low, HWMoniter shows 43, 37, 37 for ACPI, and the two cores.

Specs
P8700
3gb ram
160gb 5200 hdd
Intel 5300
bluetooth
DVDRW
Intel GMA

 

1. What BIOS version are you running? I suggest you update to the newly-released A15 BIOS.

2. What does Task Manager show as the CPU utilisation? If you are running Vista then it may be doing house-keeping etc which can cause significant CPU utilisation for the first few days.

My fan runs very quietly at slow speed and I have to be in a completely quiet room to heat it running. However, for much of the time it is off under light usage.

John

 

I upgraded to A15 yesterday. TM shows CPU utilization at under 15% most of the time. I dunno, could it have been that it was on for most of the day? Right now, the computer has been on for about 10 mins and the fan hasn't come on yet. However, my temps are higher than they were yesterday (HWMonitor).

Wierd.

 

The fan stays on for some time (> 5 minutes) once one of the triggers (not just CPU but also other sensors) has started the fan. If you check the temperatures after the fan has started then you have missed the high point in the temperatures.

John

 

My specs:
e6400 T9600/4gb/500gb/1440x900/160nvs
and
e6500 P9500/4gb/500gb/1440x900/160nvs

e6500 fan is on after ~5 mins of start and always on, temps are: cpu 46c/gpu 44/hdd 42 (fan is on)
e6400 fan is on after ~40min of start and can be switched off if not under load, temps are: cpu 40c/gpu 51/hdd 39(fan is off)
Both systems are running same software(cloned).

 

I think that difference in fan operation is a consequence of the different thermal properties of the CPUs. Most people are aware that the T series has a higher maximum power rating (35W) than the P series (25W). What few people know is that the P series have lower power rating through the whole operating range including idle and sleep.

John