oc_faq

I was wondering how to do this myself so I thought i would do a bit of research. Filip has written a guide on overvolting fans to make them faster (but louder) so here is a guide for those people who would prefer a quieter PC like me.












A Molex passthrough wire (your fan should have one built in)
Tweezers
Electrical Tape
Scissors
Wire Strippers (If you have them)

Please do not be put off, it really isnt that much work!

Your fan should look something like this one.


How It Works

This trick works by rearranging the wires in a molex connector. By default the yellow wire carries 12v of charge and the red wire carries 5v. When you hook a fan up to these it operates only on the 12v pin. By using the 5v pin to take some of the current away, you end up with the fan only using 7v of current. Genious!

What Do I Do?

This is an image of what your molex connector should look like before and after the mod.



As you can see you have to move the negative fan wire to the red molex pin. Doing this is relatively simple.

Firstly use your tweezers (or your special molex pin taker outter device if you have one) and take out the black molex pin closest to the yellow (the one with the negative fan wire on). I found the easiest way to do this was to squeeze in various places from the top whilst gently pulling from the bottom. Eventually you will hit the right spot and it will come out.



Now use scissors to cut the black fan wire from the molex pin as far up as you can. If you think you can, then just pull the fan wire out, but be careful not to damage the pin or the other wire.

Next use your wire strippers to strip the top of the wire off. I never had strippers so I used scissors. If you are using scissors then wrap them around the wire where you want to cut it and gently twist them, giving them slight pressure if you have to. Then pull the top of the wire off.

Next repeat the earlier step to take out the red molex wire (not the red fan wire). When this is out you have to attach the black fan wire to the red molex pin. I did this by slipping it under the top of the pin. Here is a picture but it is quite bad, I'm not sure you will be able to see it.



Once this is done and you are sure the wires are conducting then wrap the bottom of the molex pin in electrical tape.



Now put both the pins back into the molex head and make sure they click into place. If you have trouble puttin them in like I did then find the ends of the molex pin and bend them out so it forms an arrowhead spike. This should stop them coming back down.




You can now hook your fan back up to your system BUT!!!

When you perform the 7V trick, 5V has to go somewhere right? Yes, it may end up going back to your PSU and damaging it. For best safety you should use your passthrough molex connector and put something else on the same power line such as hard drive or CD-ROM. These devices are capable of taking the extra power. It is not absolutely vital you do this but i would recommend it.

There you go! Your very own modded case fan. I did this to an 80mm fan and it was SILENT!. i am not joking I could not hear it at all. Bear in mind that slower fans will shift less air so always check your temps when you boot back up with this mod.



Contributed by Stevo3

Stevo3

edit:
i have now done this to my 120mm fan and the noise difference is amazing! definately worth it for anybody who wants to give it a go.

Madkat

omg i cant do this LOL i broke the red connector trying it LOL...... i cant get the pin out of it!

Stevo3

you mean you cannot get the red pin out of the molex?? try squeezing it in difereent parts whilst pulling from the bottom, if that doesnt work just yank it lol!

Madkat

if you yank it, the wire comes out but not the pin :) so i just made it a 3 pin connector and it works

|talian $tallion

Thanks man, this worked well and wasnt too complicated.

PS you could always solder for a better hold insted of using tape.

Stevo3

yep, the general idea is that you do use soldier but it sounded complicated and i dont own a soldering iron!! tape does just fine anyway ;)

Ghent96

This is an extremely dangerous mod, I would never, ever recommend doing this to anyone, even an advanced user. You must clearly like burning out a lot of your computer bits, mustn't you? If you're just wanting a lower voltage fan, just use the 5v red wire input and black negative output. Much safer, quieter, you'll just have to watch your temps and not OC.

Mr. Mumbles

ahh...why is it dangerous...? But great FAQ worked great!

ShawnMcGrail

Okay, I did this trick to one set of 120 sunons in parallel, and it worked fine. I tried doing the EXACT same thing to another set of !20 sunons (also in parallel) and it just stops me from booting. I un-plugged the one set of fans and the computer worked fine, any ideas?