WARNING INCORRECT INFO ABOVE
The sticker on the console is a MAXIMUM SURGE rating which has almost no bearing on continual power usage - on many appliances this rating will be over 10* the typical continual power usage.
REAL Approx continual usage is shown below.
PC (dual core+GPU ~=RSX) 200watts
PS3 (old 60 and 20GB models ) 195watts
XBOX360 180 watts
Wii 20 watts
PS2 (guessing here ) 10 watts
Newer PS3's use less around ~155watts (65um CELL, no PS2 hardware, smaller 65um GPU) and
new Xboxes also use less ~140watts at a guess.
And the power use will gradually improve as they move to newer smaller chips.
With 45 um for CPU and GPU i would expect under 100Watts for both PS3 and X360.
Yes Wii was ~10 x less power than early PS3's and ~9 x less than early X360's.
PS3 number 1 fan







