PWM1 and PWM3 are linked and do the same thing?!

Control: management of fans, temp/rpm monitoring via soft/hardware

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holybob
Posts: 4
Joined: Mon Nov 12, 2012 2:57 am

PWM1 and PWM3 are linked and do the same thing?!

Post by holybob » Mon Nov 12, 2012 3:07 am

Hi all,
Just got new mobo (Gigabyte FA-F2A75-D3H) - I'm sure there's a firmware bug because fan control on CPU and SYS_FAN1 works fine, but I can't get any control over SYS_FAN2 and SYS_FAN3 connectors on mobo. I've reported this to Gigabyte.

Anyway..... I'm using Speedfan (and have for years). It detects 3 controllers (PWM1, PWM2 and PWM3). PWM2 controls SYS_FAN1, but PWM1 and PWM3 do exactly the same thing (control the CPU fan) and the fan operates at the lower of the two speeds.

Obviously I can make the problem irrelevant by just leaving PWM3 at 100% and hiding it within Speedfan. But my question is this: do you think this is a speedfan problem, or a mobo problem (and hence probably related to the bug I've already reported).

And actually, my second question is: if the mobo allegedly has the capacity to control 4 fans, should I not see 4 controllers in speedfan?

For the record, it's speedfan 4.47.

Cheers,

Bob

lodestar
Posts: 1683
Joined: Fri Aug 05, 2005 3:29 am
Location: UK

Re: PWM1 and PWM3 are linked and do the same thing?!

Post by lodestar » Mon Nov 12, 2012 12:09 pm

Gigabyte have improved the BIOS fan controls on most of their more recent motherboards, adding a Silent mode and sometimes also a Manual option. If you use the BIOS controls does this allow all four fans headers to be controlled? Does Gigabyte's own supplementary fan control software, EasyTune, work on all of them? If the answer is yes to both those questions then this is a SpeedFan issue, not a Gigabyte problem. Incidentally, it does not always follow that the chassis fan headers can be controlled individually. It is possible that on this particular motherboard there is control over the CPU header but SYS_FAN 1/2/3 are controlled as a group. Looking at the BIOS will confirm whether this is the case. It might at least in part also explain the difficulties with SpeedFan.

holybob
Posts: 4
Joined: Mon Nov 12, 2012 2:57 am

Re: PWM1 and PWM3 are linked and do the same thing?!

Post by holybob » Thu Nov 15, 2012 1:35 pm

Hi, thanks for your reply.

I'm in dialogue with Gigabyte - it seems like a bug with the mobo because easytune only detects 1 sys fan as being controllable (see attached smart.jpg) whereas it quite clearly can SEE all 3 sys_fan headers because the speeds are being monitored (hwmonitor.jpg).

In the BIOS, there are two sets of options: 1 for the cpu fan header, and 1 for ALL 3 sys fan headers - i.e. you can't set different properties for the sys fans individually.

Speedfan can take control of the fans regardless of the setting in the bios though.

It all feels like a Gigabyte bug - so far they've been really responsive getting back to me so we'll see what happens. At the end of the day, I've already ordered a header splitter to control both my sys fans from sys_fan1 (I'm happy with them both running at the same speed) so it isn't exactly the biggest problem in the world, but I'll be a lot happier if it gets resolved.

Bob
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