Hey I had a question, I wired up my 12v neons and switches and all into the yellow wire on the molex connector off the 12v rail on the mobo. It works fine. Then I tired plugging it to the red wire on the molex and it didn't come on. My initial thought was that the red wire must only be 5v because my little LED did work, but I don't know. Do any of you know? I don't have a multimeter unfortunately.

your are correct ruger the yellow is 12v and the RED is 5v.

Yes, and consider yourself lucky for not discovering this the OPPOSITE way; by trying to connect something intended for 5V (or less) to the 12V side (such as LEDs)...

You will also find that the usual two black wires are both ground.

The 12V + the 5V was giving you 7Volts BTW.

That is the basis of what is known as the 7Volt mod for reduced power fans.

coel, ive done that..

i went to radio shack to buy some LED's and soem soldering equip. and forgot all about buying a mollext connector.

so i get home and snip one off of an old cpu fan (very old)

i was thinking the whole time in 5v, but forgot to realize this molex conn alrdy had a splice into the 12v wire.

my 3dollar blue 2600mcd LED stayed lit for atleast 10m on the 12volt, even though it was rated at 3.7V

but then it burnt out.

For just a few bucks you can buy a http://www.happcontrols.com/tools/11030006.htm!]molex extractor tool[/URL] , pins are dirt cheap and you then can make all your wires the right length and no solder involved. I think the extractor was like $4 USD and a crimper is like $8 USD.
Some of those "must have" tools for modders.

Quote: Originally posted by Slug my 3dollar blue 2600mcd LED stayed lit for atleast 10m on the 12volt

Dude, you're paying too much for those LEDs! I paid about a dollar (Canadian) for mine.

Quote: For just a few bucks you can buy a molex extractor tool, pins are dirt cheap and you then can make all your wires the right length and no solder involved. I think the extractor was like $4 USD and a crimper is like $8 USD. Some of those "must have" tools for modders.

Gee Insom, I'm even too cheap for that! I use one of those really fine flat screwdrivers (the kind you use to fix glasses, the blade is only about 2mm wide) to push in the tabs, then I gently pull out the Molex pin. I bend the tab back out before re-inserting, and it snaps right back in. Damn I'm a ch33p-ass...

hmmm coel, were u buy yours at? at radioshack?

i just go there because its close and i dont have to wait (if im in the mood for a project, i wanna do it then)

Heck no, I find Radio Shack more like Ripoff Shack. They were selling plain-Jane low-CFM 80mm fans here for $23!!! I bought something similar at a local electronics store for about $10. (All prices CDN.)

If you know exactly what you want, i.e. "I need some 5mm 20 milli-amp high-intensity blue LEDs that draw about 3 volts", you could go to any electronics supply store. They got TONS of LEDs sitting in bulk by the box-full, but you gotta know exactly what you want. I bought high-intensity red, normal green & red, high-intensity blue (I think all blue LEDs are bright) and even some bright white LEDs the last time I went to a store like that. They didn't have purple ones, unfortunately. The white ones cost the most, at about $2.50 each..Canadian.

Look in the Yellow Pages for Electronics and make some phone calls. Computer modding is becoming a bit more commonplace now, and these places will most likely know what you need.

i see, thanks for the tips.

wow thanks for the replies/ answers guys. I figured it must be 5v on the red.

Oh, to answer someone's Q The LED I have is the High intensity 2600MCD Blue one at radio shack. I have it running with a 680ohm resistor off the 12v line and it works great!

Coelacanth, I do the same thing... I dissasemble my molex connectors using a safety pin that's been filed to blunt the tip and I bend the pins back out to snap them in. Cheaper than buying a tool, I guess!
Follows my chart below:

(me+tool)......(me+money)
______.....<...._______
$$$$$$..............Work


^my amazing chart.... I can't figure it out either, but I know the end result, without a doubt!

since i bought blacklight cold cathodes i put my old neon light in my locker. so far all good coments and no it looks like a gay disco. i built a 12 volt pack out of AAs and shrinkwrapped it. yes yellow is 12 volt normaly and red is 5.

Quote: Originally posted by carbongraphite yes yellow is 12 volt normaly and red is 5.

Why, thank you for being the fourth person to clear that up! Up until now, I wasn't quite sure...

yeah the yellow is 12 volt and the red is 5 on most power supplys

Just for your info, Coel, the Yellow is 12V and the Red is 5V on most power supplies - in case you were wondering. The black is what we modders call a "ground wire". Oh yeah, that little white thingy at the end is called a "molex connector" - again just in case you were wondering.

/smartass on

Wow Coel, you didnt know that the yellow wire is 12volts and the red is 5? Im glad I could be of service. And in case you were wondering, the black wire is a ground wire

/smartass off

Sorry i couldnt resist =)

im not sure if im correct, but i really think that the yellow is the 12v wire, and the red is 5v, you know i could be wrong so you might just want to double check that, maybe someone else could answer the question correctly

Sooo.....the yellow wire is 2 amps, the red one is dangerous, and the black wires are 120V AC, right?

Yup.