I'm building a new computer, the main components would be: -AMD Phenom II X4 965 Black Edition -nVidia Geforce 560 GTX Ti -4GB RAM 1033 MHz (Kingston) -HDD -DVD RW I'm buying the components online and one of the vendors offered me this PSU, saying it would run my system just fine: http://steel-psu.com/pro_series.html (It's the 800W one) but I've learned to never trust what online vendors say. I don't know a lot about this, but I learned that the amperage on the 12v rails is the most important thing to look at when getting a PSU, the problem is I don't know what I need there since the only calculator I found that would give that information is not free. Thank you.