Folk don’t seem to know the most basic of Voltage and Current Vs Power.
ANY circuit needs a certain amount of Voltage to function, this is specified, i.e. 12V.
The Voltage appears across the device, Happy Days.
When the circuit if functioning correctly it will draw a certain amount of Current.
The amount of Current multiplied by the Voltage is the power drawn in WATTS.
So as long as the Voltage is correct and the available Current enough the circuit will draw the correct power.
If the Voltage goes up a little, the current will sometimes drop, the circuit taking the same amount of power.
However this is not always true and the current may increase too and hence the circuit will dissipate more heat.
The Voltage does not have to be exact as any 12V circuit will work from 10-14V perfectly well as they’re Analog circuits, however 5V cant be any lower than 4V5 and no more than 5V5.
Remember Voltage is offered across the circuit and the Current is drawn.
So you can use a 12V 1000A (12000W) PSU if you want!