Fan header issue with my EX58-UD5

mogwai · 4 Oct 2010 at 22:31

I have just been checking over my build ahead of sticking the OS on it etc. The one issue I have is that when I plug one of my Akasa Apache Blacks into the SYS_Fan 2 (1 of the 2 4 pin headers), the fan spins up initally and then seemingly just sits there trying to start turning again.

The motherboard in question is a Gigabyte EX58-UD5. I have tried another Apache and the same thing happens. I have also ruled out the 4 pin extension cable that I have got to allow the fan cable to reach the header.

Initially I thought that it was the Smart Fan Control, so I went into the BIOS and turned it off but this made no difference.

Has anyone got any ideas?

thingemajib · 4 Oct 2010 at 22:35

could be that even though smart control is off, there might be some basic PWM active, and the system has not heated up enough to warrant the fans speeding up (or in this case starting up...)

dont suppose theres any options in the bios you can twiddle? start temperatures, PWM start values, speed increase intervals etc?

mogwai · 4 Oct 2010 at 22:39

All I can see is that if Smart Control is on you can then use Auto, Voltage or PWM.

mogwai · 5 Oct 2010 at 08:37

Is the rocking motion of the fan how PWM keeps the fan when it thinks that it doesn't need to be used?

1Day · 5 Oct 2010 at 12:07

If you wish to have the fan running at full speed I would suggest using a three pin header. The blue wire out.

This is on a UD9 board but you can see what I mean about the blue wire.

mogwai · 5 Oct 2010 at 13:10

From another thread in the cooling forum it seems that the issue is not PWM releated. The issue is that the SYS_FAN2 is only 5v rather than 12v.