System fan FULL SPEED

[peikko69]

So yea, after I put my pc back up with a new mobo, the system fan is running 100% speed 24/7. I don't know how to fix this. SpeedFan did not work for me. The fan is at rear of the chassis blowing air out. (cold air, all temps are fine) I tried to change the fan settings in the BIOS, but nothing happened.

 

[Karadjgne]

It may depend on your new motherboard and what fans you are using. Some motherboards such as some of the Gigabytes have reported an inability to control system fans. Also it's possible that you have that particular fan mounted to cpu_aux, or sys_alt or some such, and om more than a few boards this is a non-adjustable header, just a 100% duty cycle full 12v header. Without more specific information as to what motherboard, fans, headers or molex connections are used, I'd say it's really impossible to determine an accurate response.

 

[Emeric Francis]

if your using a Gigabyte MOBO often they will have support for gigabyte own fan control software, System Information Viewer (SIV) heres a download link if you are using a Gigabyte MOBO most of them will support this software http://www.gigabyte.com/MicroSite/369/images/system-tweaking.html#siv. If your not using a Gigabyte MOBO i would be guessing that your motherboard does not support fan control either that or its faulty. Another reason could be becuas your mother board might be trying to send your fan a command to slow down rather than dropping the voltage so if your fan dosent support being told to slow down it wont work.

 

[peikko69]

The mobo is MSI A88XM-E45. Its just a stock fan wich came in a HP prebuilt desktop. Connected with a 3 pin connector (same as on the old mobo) It registers as a system fan. It did a few times slow down, but just for a few seconds. Its pretty loud even tho its a small fan :/

 

[Karadjgne]

Check the duty cycle in bios for the header that fan is connected to. If it's set to max or performance it'll see high speeds. Also, make sure it's on a sys_fan header not cpu_aux, which can be the closest header to the rear exhaust with sys1 up top right next to cpu_fan