U mean, let's say i supply 5v to the 555, the output is 3.3v (from the datasheet). 600mW is dissipated by the 555.
No. A 555 barely works with only a 5V supply. Its max current is about 100mA and its output voltage is 3.3V. Therefore it would dissipate 170mW and a 33 ohm load would dissipate 330mW.
Let's say the load is 330Ohm, 0.5A*5V=2.5W, 600mW dissipated by 555, 1.9W by the load.
No. The output voltage would be about 3.5V and the current in the 330 ohm resistor would be only 10.6mA. Therefore the 555 dissipates 24mW and the resistor dissipates 56mW.