Power supply question

SG-118

Commendable
Jun 15, 2016
66
0
1,630
Hi just wanted to know something about power supplies since I am going to be buying one soon (the components).
Basically would a 1000 watt power supply always be outputting that amount, or lets say that the max amount of power draw the pc takes would be around 650 would it only be power that amount also would the electric bills be higher if a 1000 power supply be used to power a 650 watt pc or a 700 watt pc power a 650 watt pc. I know this question doesn't make that much sense but please help.
 
Solution
far as i know it only draws the power needed so no it wouldnt always be drawing 1000w

though the efficiency of the power supply also matters

so if the pc needed 650w you would be drawing a bit over that from the wall