Need help with speedfan and cpu fan

slpnshot

Senior member
Dec 1, 2011
305
2
81
I'd appreciate any help you guys can give regarding my problem.

Currently, I have my cpu fan connected to my cpu header. It's a PWM fan and my board has a 4 pin header and it can run in both PWM/voltage control.

The problem is, the fan is spec'd to max out at 1300 rpm but when I use the manual fan control through speedfan, it maxes out at 700 rpm. I thought maybe the rpm gauge might be faulty for whatever reason, so I plugged the fan to one of the 3 pin fan headers on my mobo. Now speedfan showed the fan running at 1300 rpm and the fan itself was noticeably faster/louder in it's operation.

Does anyone have any insight on why my fan is unable to get the max rated rpm when plugged into the cpu header? Keep in mind that I was running speedfan in manual with 100% PWM when I plugged it into the cpu header. The fan in question is a Thermalright TY-140 in place of my CM 212+ fan if it matters.
 

slpnshot

Senior member
Dec 1, 2011
305
2
81
Well I have a gigabyte board and with touchbios I see that I have 3 cpu fan options.

CPU Smart Fan Control - Normal(other options Silent/Manual/Disabled)
Slope PWM - 1.75 PWM - grayed out with normal option.
CPU Smart Fan Mode - Auto(other Voltage/PWM)

Interestingly enough, today my fan shows 900 rpm~ when I set it to 100%.
 

Cerb

Elite Member
Aug 26, 2000
17,484
33
86
Does it change at all? It's not uncommon, outside of Asus or ASRock boards advertising fan control, for all but the CPU to either read-only outside of the BIOS, or require a special BIOS setting to be controllable (such as manual, maybe?).

So, if manual didn't work, try the disabled setting.

If that doesn't work, maybe Speedfan doesn't support that chip/config. In that case, you'll want to choose the BIOS control scheme that works best, instead of Speedfan controlling it. The motherboard itself can get the max speed from the fan, but if set to any speed adjusting scheme, it won't do so unless the temperatures rise high enough to need it to.
 

slpnshot

Senior member
Dec 1, 2011
305
2
81
Ok. I was able to solve the problem. Setting the mobo to have smartfan disabled seemed to do the trick. Now 100% on speedfan has the fan running at 1250rpm. Thanks for the reply guys.