Alright guys, some of you have a lot more knowledge then me in the PSU area, so if you could help me out here, I'd appreciate it.
I have a Saturn on order, which I plan to upgrade to Jupiter once they start offering the modules separately. The PSU that I have picked out seems like a perfect fit to me, and at a fairly good price. If you guys could look it over and let me know, that would be great. And if it is a good one, it could turn out to be a good deal for everyone.
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139011Should be the minimum acceptable wattage for a power supply. I'd recommend going with something around 1kw... They are much more efficient at 50 % load versus 80 - 90 % load.
That hasn't been true for the last decade but it is a myth which dies hard.
The minimum efficiency for an 80-Gold PSU is 90% at 50% load and 87% at 100% load. The curve is very flat.
For example here is the test for the PSU linked to:
http://www.plugloadsolutions.com/psu_reports/CORSAIR_CMPSU-850HX_ECOS%201464_850W_Report.pdf50% load = 90.38% efficiency
75% load = ~90.0% efficiency (estimated due to their horribly low res chart)
100% load = 87.06% efficiency
So using a larger PSU would save you maybe 1% in power, 3% under the extreme example of 100% load vs 50% load. At 1% power on 600W 24/7 would save you 53 kWh per year. At $0.10 per kWh we are talking $5. Spending $50 more on a PSU makes the break even 10+ years. At once time PSU were pretty shitty with narrow "sweet spot" (40% to 60% of peak power), and efficiency tanked (<70%) outside of that. This is where the advice of buy 2x the needed power. Those days are long gone thanks to the 80 Plus program and even lower end 80Plus PSU have an almost flat efficiency "curve" for loads anywhere from 20% to 100%. It is nice companies keep making more and more efficient PSU (Platinum and Titanium are also possible) but once you get to ~90% it starts being diminishing returns. Still Google and facebook use custom PSU which only output 12V to get 95%+ efficiency. Really there is no reason for PC PSU to be as complex as they are. Maybe some future standard will improve that.