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  #11  
Old 02-02-14, 05:37 PM
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Feronix Feronix is offline
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Where are ya located mate?

Bitfenix do some nice braided/sleeved Molex > Multiple 3 Pin adaptors in 12/5/7 volt. Also in different colours of sleeving.
http://specialtech.co.uk/spshop/cust...tegory=&page=2

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  #12  
Old 02-02-14, 05:52 PM
Junit151 Junit151 is offline
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I don't have the fans yet, I'll be getting two included with the H80i. As they come included with the AIO I don't know if they come with reducers.

EDIT: The 120's included with the H80i do NOT come with reducers.

Feronix: I was going to do the whole braided cable thing but since I'd try to hide my fan cables anyway I don't want to show them off with fancy cables, I'll just tuck them behind when I get a proper case and use extension cables if needed.
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  #13  
Old 02-02-14, 06:04 PM
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Remmy Remmy is offline
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Quote:
Originally Posted by Junit151 View Post
I don't have the fans yet, I'll be getting two included with the H80i. As they come included with the AIO I don't know if they come with reducers.
Oh I see, I thought you had them already
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  #14  
Old 02-02-14, 08:10 PM
jamesriley94 jamesriley94 is offline
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I wouldn't use resistors these days myself since if you put more than a couple of fans through them they get very hot.

I don't see a problem at all with 7v wiring these days. PSUs these days are generally high enough quality that they aren't effected at all.

Get one of the Bitfenix ones like Feronix suggested. That way you can always swap the pins over and change them to 5v, 7v or 12v with a thin screwdriver of a pair of tweezers or something.
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  #15  
Old 02-02-14, 09:28 PM
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Davva2004 Davva2004 is offline
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There's absolutely no problem with taking a 7v feed from a molex connector, because of the way electricity works. The idea that you're somehow forcing spare volts back down the 5v line to the PSU just simply isn't true.

Voltage works on the difference between two wires. So to get 12 volts, you have 12 volts down one wire and zero volts down the other. The difference between the two is twelve, hence twelve volts.

So if you have one wire with 12v and one wire with 5v, only 7 volts flows between them as that's the difference between the two wires. That's how you can run a fan at 7v, and the PSU doesn't have a single problem with it at all.
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  #16  
Old 02-02-14, 09:51 PM
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Originally Posted by Davva2004 View Post
There's absolutely no problem with taking a 7v feed from a molex connector, because of the way electricity works. The idea that you're somehow forcing spare volts back down the 5v line to the PSU just simply isn't true.

Voltage works on the difference between two wires. So to get 12 volts, you have 12 volts down one wire and zero volts down the other. The difference between the two is twelve, hence twelve volts.

So if you have one wire with 12v and one wire with 5v, only 7 volts flows between them as that's the difference between the two wires. That's how you can run a fan at 7v, and the PSU doesn't have a single problem with it at all.
The problem isn't the voltage being forced into the PSU because that doesn't even make any sense. It's perfectly fine setting it up the 7V potential over the fan using 12V and 5V, the problem (if any) arises in the current flow. If you make the fan run like this, current must be going into the PSU down the 5V line which is opposite to what it was designed to do.

Edit: PSUs should have protection circuitry on their outputs, and if the current into an output was greater than the current out then the PSU ought to just shut down as a safety precaution. People report this exact thing happening with certain PSUs when they do a 7V molex mod. As long as you have enough load on the 5V line, so a decent amount of current is output, the relatively small input current from the modded molex won't be enough to do anything, but if it isn't then the PSU shuts down.

Just in the interest of safety, either do a 5V mod, or use resistors, you won't cause any problems doing either of those.
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