Board: B85N Gigabyte ITX board.
SG-05 case so using the stock front fan, which is 3 pin. The CPU fan is a PWM Nexus. The board has 2 4-pin connectors. In the BIOS, I can se either fan to run: Normal, Silent, Full (IIRC), and Manual. Under manual I can specify a percentage? of the fan's potential speed. Stating variables from .15 to 2.5 PWM. Something like that.
The CPU fan ramps up during games, but according to a CPUID HWMonitor, there are no pwm fans connected, the two connected are listed simply under "fans" rather than "fans PWM". Is there a way I can verify how the fans are being controlled? Maybe I should swap the Nexus for a 3-pin if it's not even using PWM to control the cpu fan. Could the front 3-pin be causing it to default to voltage regulation for both connectors somehow? Hmm.
Is my motherboard controlling fans via voltage? not PWM?
Moderators: NeilBlanchard, Ralf Hutter, sthayashi, Lawrence Lee
-
- Posts: 94
- Joined: Mon Apr 30, 2007 1:55 pm
Re: Is my motherboard controlling fans via voltage? not PWM?
http://download.gigabyte.eu/FileList/Ma ... b85n_e.pdf
Looking at the manual for that board, the CPU_FAN has the fourth pin listed as 'speed control', whereas the SYS_FAN is listed as 'VCC' (with 'speed control' grouped in with the 2nd +12v pin). My assumption here is that the CPU header is genuine PWM and the system fan header is voltage control. Only a guess though, but it certainly points towards two different methods of speed control across the two headers.
Looking at the manual for that board, the CPU_FAN has the fourth pin listed as 'speed control', whereas the SYS_FAN is listed as 'VCC' (with 'speed control' grouped in with the 2nd +12v pin). My assumption here is that the CPU header is genuine PWM and the system fan header is voltage control. Only a guess though, but it certainly points towards two different methods of speed control across the two headers.