We have a 650w PSU on our first build to go along with a MSI 560 GTX Ti GPU. My Dad believes the graphics card might need its own power supply, but I explained to him that the reason we bought a higher wattage power supply was to fuel the graphics card. A little help here? He is VERY stubborn to the point he needs to "see to believe". What should I tell him?
the power supply has a few different cords. the GTX 560 ti requires 2x 6 pin (or PCIe) connectors, which look like this : http://techreport.com/r.x/psus-0907/pcie-connectors.jpg there are 6 pin (left picture) and 6+2 pin (right picture) the 6+2 is the same as a 6 pin, just an extra 2 incase you have a very power hungry card. but yes, you are correct. the power supply powers everything in a computer, your dad is very wrong. make sure you have 2 of those cords. if you do, you are fine. if you dont, you will have to get some molex to PCIe adapters. which look like this : http://bigbytepc.net/images/molexpcie.jpg you can get them online everywhere for a very cheap price. but if your PSU doesnt have them, order your gtx 560 ti first, most the time they come with 2 of those adapters for people like you. enjoy your "TOLD YOU SO!" feeling!
your dad is thinking more of the old days and wattage of the whole system and old hp/dell with under size power supply's. sit down with your dad and show him with a few online power supply cal programs that the mb/hard drive and video card are under the wattage of your power supply. just remember to check to see how many 12v rails the ps has. if it has two 12v rails look to see what the max amps are per rail. a lot of fried pc or pc build issues is a video card that near or over the amp rating of the 12v rail.