Arduino Mega - 54 or 64 digital pins

[R_Gol]

@Wawa

The Mega MCU has four VCC/GND pins, which allow for 100mA each, so 400mA absolute max chip current. So you're ok with 2.27mA per pin.

Using 60 transistors could be a nightmare. Is this for your 12volt/3watt LEDs?
2.27mA seems too low for a 2N3904 to fully saturate with 250mA collector current.
Leo..

The 60 transistor is for driving 60 individual 10mm LEDs. not for 12V/3Watt LEDs.
I have already drive 40 of them with 40 2N3904 using 2k2 resistor from the Arduino GPIO pins to the transistor base. it seems to work just fine/