Which wires should i use, image inside

[rlehm]

Looking to light up my illuminated buttons. This is what my wiring to my dvd player looks like. The yellow, is 5volts for sure? Don't want to ruin my computer. And is either black ok for ground? Then, on these NovaGem buttons, is the side with the fat protected wire end power, and the skinny one ground, or is the skinny one power, and the fat one grnd?

[MonMotha]

Standard PC color coding is:
RED: 5V
YELLOW: 12V
ORANGE: 3.3V
BLACK: GROUND (power common tied to the earth line on the AC plug)

There's usually a sticker on the supply that details this, so verify if possible, but I've only once seen a PC supply that departed from this, and it was ancient.

Oh, a few more things: Note that this is not the same as what is fairly standard for arcade wiring, which uses orange for 12V.  Also, if you have a multimeter, USE IT.  Just check DC volts between the color of interest and black.

[rlehm]

So use the red wire, and either black will do. thanks.