I'm no electricial. A little help please.

[Inteless]

When considering fans which run off the motherboard, what's
the most important factor to consider: volts, amps, or watts?
Reason I ask, I'm considering modding my case for 120mm fans
front and rear. Don't really need to, just want to. I would
want to run the front fan off the mobo although I could run
it off 4 pin if I had to.

thanks

Inteless
---------------------------------
Abit KT7A-Raid (with blue orb on northbridge)
Duron 600 @ 1000 (142 x 7)
OCZ GeForce2 MX (with blue orb, ram sinks, 5.5ns ram, 220 core/210 memory)
256mb Crucial PC133 CL2 (1)
IBM 7200 rpm ATA100 (IDE Raid)
AWE64 Audio
Kingston 10/100 NIC
Home made rounded cables
OCZ Monster II cooler w/Everflow 60x60x25 26cfm fan
Sunon 80x80x25 42.5 cfm case fans front/rear
Idle temp 37C @ 23C ambient
Load temp 42C @ 23C ambient w/Sandra burn in

 

[enginjon]

What you have to watch for is the Current drawn by the fan. If you use the 3-pin header on the MB, check you MB manual to see what the max current can be drawn from that header. If it is higher then the draw of your fan, you are ok.

 

[Inteless]

<< What you have to watch for is the Current drawn by the fan. If you use the 3-pin header on the MB, check you MB manual to see what the max current can be drawn from that header. If it is higher then the draw of your fan, you are ok. >>



Thanks, but uhh, how do I know how much current it draws? All I see
on the fan specs is volts, amps, watts, cfm, yadda yadda.
I told you I was no electrician!

 

[enginjon]

sorry, current is measured in amps (A), so the amps drawn by the fan have to be less than what the motherboard can supply, or else you will burn out the pins on the motherboard

 

[HaVoC]

Volts x Amps for a DC fan = wattage. So divide the wattage by voltage and you will get the amperage drawn by the fan.

 

[Inteless]

it all makes sense now. thanks to both of you.

Inteless (or is it Clueless, I forget)