fan question

[pby5cat]

from a cold boot, if i put a 12v fan on 5v will it start? Also if it doesn't start will it hert the fan by having 5v runnung throught it and no spinning? Will a fan start a 7v? i know the larger the fan the more volts reqired, so lets say 80mm panaflow 3500rpm.

 

[madsam]

you either want to do a 7 volt mod to cut back the speed, or use a rheastat to adjust the speed manually. most fans are rated 7v to 12v. if you tried 5 volts, it would probably put too much drain on your 5 volt rail, but even so, you said 5v and no spinning? yes, i think you are looking to fry the fan, or worse. you can try 5 volts if you like, but i don't recomend it.

why do you want to use the 5v for your fan? and are you doing this off the fan headers on the motherboard?

 

[Liss]

you can run 7v or 5v on almost any 80mm fan.. but when trying to run 120mm fans at 5v it won't start.. and most CASE fans run 12v..

 

[pby5cat]

ok 5v won't work, will a fan start a 7v using the same example?
i was thinking with the 5v a won't start, so if i need that fan i push a normaly open switch as like a starter that gives the fan 12v, but that might hurt the fan.

 

[juliendogg]

every fan that i have, or have tried, works fine at 5v or 7v. i've run my 120mm fan at 5 volts, pretty quiet but it didn't move much air. it's at 7v now, as are most of my other case fans, and they all start and run just fine, without very much noise