01-26-2012 03:05 PM
I have conducted a couple simple tests to see how the cooling fan operates with the bios setup configurations "Fan set to fan always on" to either "Enabled" or "Disabled".
My system is a HP Pavilion G7 1167dx with AMD Phenom II P960 with 4 gigabytes of Hynix memory at stock settings. Bios version F.43. OS is Win 7 Home Professional. Cpu multiplier x9. Ht clock 200mhz. Cpu power saving options turned off.
The only modification to the cpu cooling system is the polishing of the heat sink contact area and application of Artic Silver Ceramique2 heat sink thermal coumpound.
Temperature monitoring software I used was "Core Temp 1.0"
100% cpu loading was provided by "HyperPi .99" @8M.
The first test was done with bios configuration setting "Fan always on" set on "Enabled".
Room temperature was 70f and after starting "Core Temp" and loading "HyperPi", the cpu temperature was allowed 20 minutes to stabilize at 42c.
Throughout the test the fan ran consistantly at low speed.
When the test completed the highest cpu temperature was 59c.
Next, I rebooted into bios setup and set the "Fan always on" setting in bios to "Disabled".
Rebooted and ran "Core Temp" and loaded "HyperPi". After a 20 minute stabilization period the cpu temperature hovered around 50c.
During the test the fan came on high at 55c and ran at medium speed and periodicaly switched to high speed throughout the test. After the test completed the fan ramped down to low speed and shut off at 47c.
My observation: Regardless of the fan setting in bios: No difference in cooling capacity with cpu loading at 100%.
Fan noise is barely audible with the fan always on setting "Enabled". With the setting of "Disabled", only when the fan speed jumps to high was the sound noticible.
* I did not run this test prior to fixing the heat sink conditions but during the same time the notebook seemed to run pretty hot when streaming movies on Netflix.