3 pin fan header plug into 4 pin molex?

PSUs: The source of DC power for all components in the PC & often a big noise source.

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ao
Posts: 34
Joined: Wed Mar 17, 2004 9:58 am
Location: seattle

3 pin fan header plug into 4 pin molex?

Post by ao » Sat Oct 30, 2004 2:39 pm

Hey all,

The short story: I need a 3 pin header to plug my modded PSU fan into, and there's not one in reach. I'm looking for advice to get power to the fan.

The background:
Long ago I modded my girlfriends enlight PSU and stuck an L1A fan in there. I didn't do anything fancy -- the power cable to run the fan was still poking out the back, and i had to route it back in through the EMF shield on the back and into the 3 pin header on the KT7A-raid motherboard. Recently that board up and died, and the motherboard I have to replace it with (asv8x-x) doesn't have a fan header anywhere within reach of the PSU fan. Whoops.

So I either need to buy some kind of 3 pin extension cable, or convert the three pin plug into some kind of molex connector. I've done the 7 volt / 5 volt molex mods before, but that never required any soldering. Soldering little wires together like that seems like it would be a lot trickier than soldering a wire into a pcb, or something else, so I'm a little leery of doing it.

Would you all recommed buying some kind of extender for the 3 pin fan plug, or do you have advice on making a pass through into a molex connector? I see lots of advice on modding molex connectors on the web, but nothing about converting 3 pins to 4, even if it should be straightforward. I'm open to any and all suggestions, and if you recommend getting an extender, can you point me to one? I've had no luck finding where they list them at newegg.

Thanks for any advice, this forum is great.

mg1394
Posts: 167
Joined: Sun Aug 11, 2002 3:26 pm
Location: Silicon Valley

Post by mg1394 » Sat Oct 30, 2004 3:37 pm

Just use an extention cable

http://www.svc.com/123to3ex.html

for $0.99

(CompUSA has the same thing for $3, but no shipping if you have one close. Almost all computer stores that have parts have these.)

ao
Posts: 34
Joined: Wed Mar 17, 2004 9:58 am
Location: seattle

Post by ao » Sat Oct 30, 2004 4:17 pm

mg1394 wrote:Just use an extention cable

http://www.svc.com/123to3ex.html

for $0.99

(CompUSA has the same thing for $3, but no shipping if you have one close. Almost all computer stores that have parts have these.)
Sweet, that's totally what I'm looking for. All of the computer stores are far enough away that getting to them is a real pain, even when my car is working. Still not that elegant of a solution with wires running out the back of the case and back inside(do most PSU fan modders do something more slick than this???), but cheap and guaranteed to work. Shipping is 5 bucks on a 1 dollar part... I love it.

Thanks again, I haven't ordered from or visited svc in a long time, I've been pretty much a one store shopper since Newegg really got going. The last thing I bought from SVC were some of those ridiculously quiet NMB 80 mm fans. No CFM to speak of, but if you're ok with high temps...

caber
Posts: 50
Joined: Wed Oct 13, 2004 11:42 pm

Post by caber » Sat Oct 30, 2004 4:28 pm

Not sure if i can help, but I basically converted the 3-pin into a 2-pin header by snipping off the old 2-pin head and swaping the red and black wires with the 3 -pin header... makes sense?

ao
Posts: 34
Joined: Wed Mar 17, 2004 9:58 am
Location: seattle

Post by ao » Sat Oct 30, 2004 9:00 pm

caber wrote:Not sure if i can help, but I basically converted the 3-pin into a 2-pin header by snipping off the old 2-pin head and swaping the red and black wires with the 3 -pin header... makes sense?
Ehhh, I think I see what you're saying, but I'm not sure it's what I want to do. You're saying I should snip the take the black and red wires from the 3 pin connector that's connected to the fan, just grab the red and black wires from it, and plug/solder it into the original spot on the PCB of the power supply, no?

If that's not what you're saying, then you lost me. ;)

caber
Posts: 50
Joined: Wed Oct 13, 2004 11:42 pm

Post by caber » Sat Oct 30, 2004 11:36 pm

yeah.. along those lines but 1 quick question, Does your PSU inside have a 2 pin fan header? If it does then the job wont be so messy, if not... maybe soldering (thats a big maybe) with a tucked (and shortened wires) fanmate to control the RPM??

Good luck

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