Fan speed on Jump PSU

Sup guys, I need alittle help with my fans. I just set up my grow box (pc case) today and im using a 375 watt ATX PSU, I jumped it and everything but the fans seem like there moving slow, they moved more air when I had them running the PC.

Is it because maybe the OS ran the fan speeds when i had them in the computer or what, is there anyway I can get more out of them. Their really nice fans they came out of a Dell XPS I had, I'm using the same PSU that XPS was using too.TIA

Did you connect the positive fan wire to a red wire? If so, thats only 5V.. Molex connectors have a red 5V, 2 black grounds, and (usually a yellow) 12V pin..
Better yet, off the MB connector there are alot of 5V's, alot of grounds, alot of 12V, and as an added bonus there are -5V, and -12V as well.. if you're only running a fan they can supply enough current, and you can pick your voltage to be 24V, 17V, 10V, 12V, 7V, or 5V by using different wires as your ground/negative.. As long as the negative wire is put on a lower voltage wire than the positive is, it will work..

Well for the bigger fan I connected the colors that matched, it has black,white,red,blue wires, I forget what all the volt for the colors are, but I got my A+ cert book beside me so I can figure it out.Then my smaller fan has black,red,white wires. So I can connect higher voltage to the fan, even if the voltage is different?

every fan in a pc that i have ever seen can handle 12 volts and i have seen afew. You only need to connect the yellow and black, probably black to black and yellow to the fans red wire. Any other wire are simply for monitoring speed and unnessacary for our use.

P@ssw0rd

Yea, you can run dc fans off pretty much any reasonable voltage depending on whether you want more speed, or less noise etc.. AC fans on the other hand.. Never tinker with their speed unless you know exactly what you're doing.. (And ppl who know exactly what they're doing in that area, know why its WAY better to just get a more suitable fan..