I've read all over the net about the xbox slim fan running at full speed. The steps aren't so clear, from what i got was just cut the blue wire. Another one i've red was cut the blue and yellow.Im sure its just the blue control wire by its self. I'm just looking for a straight answer before i snip the wire in 2 and waste 10 sec of my time. any advice is needed... I know the fan mod is useless but in my defense this thing runs hot.
I don't think you need to do that at all, the Slim is designed to handle the heat load of the Xbox just fine. If the fan has 4 wires it uses what's called PWM to control the fan speed and will adjust it's speed according to the heat load of the xbox. If it has three wires it uses voltage regulation to change speeds.
I would advise against cutting monitor wire as it will cause you xbox to probably log a fan fail event, which may be readable by XBL. If you insist upon doing it, look the fan connector on the mother board. With the alignment tab at the bottom ( like this [_]) the pin that is at the left side will be the control/monitor pin. Cut the wire that plugs into it.
NOTE: I take NO RESPONSIBILITY WHATSOEVER for your xbox. You break it, your fault.