D865GLC + CPU Fan Speed HELP

  • Thread starter Thread starter Ron Reaugh
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R

Ron Reaugh

I have an Intel D865GLC mobo that has a std retail boxed with std Intel fan
P4/2.6 800 FSB CPU with 2x DDR400 256MB for dual channel and hyperthreading
and all enabled. I've flashed the latest P11 BIOS but the behavior
described below was the same for P09.

No matter what the CPU fan speed is 2720-2840 RPM. The BIOS setup is set
for CPU fan speed control and both low speed off and slow have been tried.
I
just got through cooling the system to where the CPU temp showed 13C(open
window[glass kind]) and RPM~2750. I've tried both inside BIOS setup and in
XP Home in Intel Active Monitor. The CPU fan runs at about 2740 no matter
what.

Sometimes the fan stops when the system enters standby. Normally the CPU
temp is about 30C and RPM~2740. I moved the CPU fan to mobo header zone 2
and at low temp the fan was stopped and at ~30C it was ~1300RPM and 1800 at
40C again both in BIOS setup and XP Intel Active Monitor. I'm guessing that
the max RPM is ~2840.

What is the normal fan speed/RPM range for one of the std Intel CPU fans
with the 3 pin connector plugged to the mobo's 3 pin "Processor fan"
header(H)?

What controls CPU fan speed: mobo hardware, mobo BIOS or some SW under
XP?

Where's the likely problem and what do I try/where do I go next?

Are they any Intel NGs providing help these days as there used to be?
 
Ron said:
I have an Intel D865GLC mobo that has a std retail boxed with std Intel
fan
P4/2.6 800 FSB CPU with 2x DDR400 256MB for dual channel and
hyperthreading
and all enabled. I've flashed the latest P11 BIOS but the behavior
described below was the same for P09.

No matter what the CPU fan speed is 2720-2840 RPM. The BIOS setup is set
for CPU fan speed control and both low speed off and slow have been tried.
I
just got through cooling the system to where the CPU temp showed 13C(open
window[glass kind]) and RPM~2750. I've tried both inside BIOS setup and
in
XP Home in Intel Active Monitor. The CPU fan runs at about 2740 no matter
what.

Sometimes the fan stops when the system enters standby. Normally the CPU
temp is about 30C and RPM~2740. I moved the CPU fan to mobo header zone 2
and at low temp the fan was stopped and at ~30C it was ~1300RPM and 1800
at
40C again both in BIOS setup and XP Intel Active Monitor. I'm guessing
that the max RPM is ~2840.

What is the normal fan speed/RPM range for one of the std Intel CPU fans
with the 3 pin connector plugged to the mobo's 3 pin "Processor fan"
header(H)?

What controls CPU fan speed: mobo hardware, mobo BIOS or some SW under
XP?

Where's the likely problem and what do I try/where do I go next?

Are they any Intel NGs providing help these days as there used to be?
Click to expand...

Hi Ron,

I've got Intel's 865PERL, 2.8gHz P4 and stock CPU cooler. It behaves just
like yours ... although I haven't tried the open-window test!! The noisy
h/s fan drives me crazy.

http://www.silentpcreview.com reviewed Intel's heat sink. They say the fan
speed is controlled by a thermistor built into the fan itself, suggesting
that the CPU fan power header supplies 12v regardless of temperature.

Your experiment with the zone 2 header seems like a good solution - my GUESS
is that the BIOS is controlling output voltage to that header, but it might
be XP. I think I'll give it a try. I'm running multiboot - Linux/Win2k
Win98/DOS so I'll know soon enough if the o/s is controlling zone 2.

What is not clear is whether moving the fan tachometer signal from one
header to another compromises overtemp protection (if any). Leaving the h
s fan connected to its intended header and putting a resistor in series
with the +12v lead might be safer. Something around 25-50 ohms @ 2 watts
seems right.

Roby
 
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