3 vs 4 pin fans

[josiahgleeson]

I recently installed the Asus b75m-plus mobo, it has two 4-pin fan slots (one for CPU and one for case.) I'm currently using a 3 pin fan for the case and the fan is stuck on max speed and I'm unable to affect it with software (including bios settings.) My guess is that I'll have to buy a 4 pin fan for my case but this issue is really confusing. Just wondering if someone can explain to me how 4 pin fans work vs 3 pin and why does my mobo have two 4 pin slots? Thanks

 

[krzyimprt]

I recently installed the Asus b75m-plus mobo, it has two 4-pin fan slots (one for CPU and one for case.) I'm currently using a 3 pin fan for the case and the fan is stuck on max speed and I'm unable to affect it with software (including bios settings.) My guess is that I'll have to buy a 4 pin fan for my case but this issue is really confusing. Just wondering if someone can explain to me how 4 pin fans work vs 3 pin and why does my mobo have two 4 pin slots? Thanks

Certain motherboards will allow you to control 3 pin fans via voltage regulation, but its only on specific headers on specific boards. Generally, 3 pin fans are meant to run at 100% speed.

 

[josiahgleeson]

Yeah but when I used the same fan in my old build it wasn't nearly as fast/loud.

 

[krzyimprt]

Yeah but when I used the same fan in my old build it wasn't nearly as fast/loud.

Probably had a better motherboard. Swap it out with a lower RPM fan.

 

[josiahgleeson]

Thanks for the help!