Default fan speed @ system power-up?

[tucansam]

Gang,

I have my new system build underway. I am testing fan noise levels right now. I have the fans installed in the case along with the power supply, and the blue and green pins jumpered on the PS header so I can power it up without a motherboard.

When I power the system up, the fans are definetely moving air and are extremely quiet. I'm wondering what their defaul speed is at this point, ie, is this the fastest they will spin (and loudest they will get), or are they running at a default slower level until something (like the MB) tells them to increase RPMs?

Thanks.

 

[hunter315]

Depends on the fans. Are they thermally controlled? Do they have a 3 pin connector for a fan header or are they powered straight off of a molex connector? If they arent thermally controlled and only have a molex connector then they have two speeds, full and stopped. If they have a 3 pin connector they likely default to their low values initially to keep from being too loud. If they are thermally controlled then they are definitely on their lowest level unless you are testing in death valley.

 

[tucansam]

Yep. Thermally controller (Schythe (sp?)) Any way I can get them to high speed to test? I'm debating a fan controller.

Thanks.

 

[hunter315]

Whats the model number on it? You can find all of the sound ratings on their fans here
http://www.scythe-usa.com/support/support_temp/002/fan_spec.html
A second fan of a matching type will increase the dBa rating by 3, you can find decibel equivilancy charts online to help you figure out how loud it will be. But if they are thermally controlled i hope you never hit full speed on them, but if you want to know how loud it will get try a hair dryer, it should get you up into 70-90C range.

 

[tucansam]

Meh. The case will get 5lbs of acoustic sound deadener added to it (Dynamat) as well as foam. I just wanted to see worst-case scenario on air flow noise.

Thanks.