psu draw question`

[powerade]

so long as ur components arent sucking up all ur power draw, does the psu draw its limit all the time, or only pull more power from the unit as its needed ?

its pretty bad when TOL vid card pulls 180 w, so im curious if my 625w psu is drawing that all the time when the pc is on

 

[Bbq]

It only draws what it needs.

Say you have a 500w psu, and a pc that draws 300w worth of load. It draws 300w + efficiency loss from the wall.