System fan and temperature

[Jim]

Recently, I put together a compact system using the Antec NSK 1380 and
Gigabyte GA-
MA69GM-S2H motherboard. Over the last few days, its been running
continuously and I've been watching the system and CPU temps and fan
speeds using the BIOS health utility. System temp has gone from 30C
to a high of 43 while CPU temp has gone from 30C to 41C. CPU fan
started out at 1800rpm and gone up to 2250 while the system fan has
stayed constant at 980 rpm. Here's my question - the Antec case and
PSU has a fan connection which I have connected to the MB system fan
SYS_FAN header and I expected the fan speed to increase with system
temp. Any reason why not?

 

[Dave]

Recently, I put together a compact system using the Antec NSK 1380 and
Gigabyte GA-
MA69GM-S2H motherboard. Over the last few days, its been running
continuously and I've been watching the system and CPU temps and fan
speeds using the BIOS health utility. System temp has gone from 30C
to a high of 43 while CPU temp has gone from 30C to 41C. CPU fan
started out at 1800rpm and gone up to 2250 while the system fan has
stayed constant at 980 rpm. Here's my question - the Antec case and
PSU has a fan connection which I have connected to the MB system fan
SYS_FAN header and I expected the fan speed to increase with system
temp. Any reason why not?

You'll have to pull out the manual for your mainboard to figure this one
out. Does the motherboard control fan speed? If so, is that option enabled
in the BIOS settings? 980RPM seems really slow. Too slow. I'd expect a
SLOW fan to run around 1500 RPM. Note I said a SLOW fan. I'd question
where you got that reading, I suspect it is off. If it's correct, I'd
wonder if the fan is defective. -Dave