plz refer back to my previous thread if u need more info.... http://forums.bit-tech.net/showthread.php?t=48438 finally got my circuit finished and added the fans and LEDs: problem is, once I bring use the pots to bring voltage up to max (just over 10v), the LEDs go thermonuclear and start fizzing and melting. The LEDs are rated at: FWD Volts: 3.3v REV Volts: 5v DC FWD Current: 20mA I have been using 470 ohm resistors as the bit-tech calculator suggests. At the moment, the circuit is being powered off my dad's 12v test supply. At around 5v the LEDs light up, around 7/8v they start to change colour - by 12v they are dead. Can anyone suggest what i may be doing wrong? My dad says the fan may have a certain amount of reverse current on it, but he's not sure. Any ideas?