Question Case fan incompatible with mobo system fan header

[408jojo]

So the fan in my pc case (Corsair 100R) is possibly incompatible with my motherboards (Gigabyte B450M DS3H) system fan header. The problem seems to be that the case fan is a x3 pin connector and that the mobo can only connect to x4 pin fans. I might not make sense since I’m new to pc building.

 

[Satan-IR]

You can connect 3-pin fan connectors on 4-pin motherboard headers. There's a small notch that only lets the user to insert the header on the right 3 pins.

The PWM feature (the 4th pin for fan speed control) will not work though and the motherboard has to regulate rotation speed through voltage alternation.

Also you have to check with motherboard manual and see if you have to change a BIOS settings for the headers to work properly with 3-pin fans.

 

[408jojo]

You can connect 3-pin fan connectors on 4-pin motherboard headers. There's a small notch that only lets the user to insert the header on the right 3 pins.

The PWM feature (the 4th pin for fan speed control) will not work though and the motherboard has to regulate rotation speed through voltage alternation.

Also you have to check with motherboard manual and see if you have to change a BIOS settings for the headers to work properly with 3-pin fans.

Do you think that I could maybe buy a molex connector that connects to my 4-pin motherboard header and for the fans it connects to 3-pin headers since I was thinking of buying two additional fans?

 

[tennis2]

You're describing a fan controller. Most of the ones like you're describing function via non-PWM signal also, so you're not changing the "problem"

Why not try what Satan-IR said first before you spend more money? A $2 2 way fan splitter is all you need to run 2 fans from one header. Some times you can do a 3 way splitter, depending on the fans.

 

[Satan-IR]

Do you think that I could maybe buy a molex connector that connects to my 4-pin motherboard header and for the fans it connects to 3-pin headers since I was thinking of buying two additional fans?

Yes, however you have to spend more and if you connect the fans directly to a Molex power hub/connector (without a controller in between - be it fan controller chip or the motherboard itself) the fans would rotate at maximum speed all the time.

You can get a fan hub with its builtin controller that let's you control the speed independently or one that connects to motherboard headers (and I guess you meant an indipendent fan controller that draw its power from a Molex connector?) and let's the motherboard control the speed.

Either way it's possible at additional cost and a little bit of extra work connecting the stuff.

 

[408jojo]

You're describing a fan controller. Most of the ones like you're describing function via non-PWM signal also, so you're not changing the "problem"

Why not try what Satan-IR said first before you spend more money? A $2 2 way fan splitter is all you need to run 2 fans from one header. Some times you can do a 3 way splitter, depending on the fans.

Btw I currently only have 1 fan in the case but I’m gonna buy 3 Arctic fans and replace the 3 pin fan I have so that all my fans are pwm and 4 pin with a 3 way splitter like you said

 

[tennis2]

Sounds like a waste of money if your mobo can [likely] control 3 pin fans via voltage control. Have you tried that to confirm? Always try the free option first.

I'd probably do a pair of 2 way splitters instead of hanging 3 fans off the Sys Fan header.

 

[408jojo]

I haven’t tried the free way yet since I’ve been at my grandparents house for a week now but I’m going to my house tonight and once I’m there I’ll try to connect the case fan onto the mobo sys fan header and if I am able to do that I will benchmark the temperature drop.