So Here's the information I've found:
Molex: First I would like to start off with where you draw the power from in a computer. The white Molex connector, it has a red wire, two black wires and a yellow. The black wires are the negative, the red wire is 5 volts, the yellow wire is 12 volts. Now if you connect the positive wire to the yellow and the negative wire to the red you will get 7 volts. So off a basic power connector, the same that powers cd roms, case fans etc. you can get 12v, 7v, and 5v.
from techspot.com forums:QUOTE
Q: I want to slow down my 3 wire fan. Which wire do I add the resistor to?
A: Both the red and black. Yellow is always for RPM monitoring...
so I have this fan I pulled off the Northbridge of an old MoBo (3 pin MoBo connector). it has 3 leads: Black, Red, Yellow. And the Fan is labeled DC 12V. Now I'm assuming that Black is still ground. But wouldn't it make sense for the Yellow to be the 12v line, so as to keep things consistent? But the techspot post says that the yellow is always the RPM monitoring connection.
Does anyone here know?
Now, since convention rarely means anything I'd accept the answer from techspot, but I just want to make sure.... it would be nice if people could follow the same convention from one application to the next....
Also here's what I'm trying to do:
I did an LED mod of the Jewel on my xbox, and I want to mount it on the fan, pop in a calculated resistance and get the jewel to rotate nice and slowly... I think it would look sweet... And an Xbox really is just a computer so this is still (more or less) on topic for these forums...
Why you should care about the PATRIOT Act.