It is what i had in hand (a 10 yr old 950W psu). A 950W psu does not mean it is sucking 950 watts from the wall all day long. It just means that it has the headroom. As i mentioned on my earlier post, it is a streaming htpc that i also use for "gaming" on a big tv at times. A single graphics card will suck 10 ish watts on idle load (during streaming) and 300 to 350 watts under full load during gaming. The xeon will use 30ish watts when streaming and 140ish Watts during gaming. Power usage will drastically vary depending on the application, but, it will be quite low during streaming. One can also undervolt the chips to further reduce power consumption on a "streaming only" optimized pc. Of course, newer hardware will be more power efficient to begin with than older hardware (i.e. you start with a low tdp chip, etc).