Do I need a bigger power supply ?

I'm building a desk top computer . These are the spec.'s --- mobo,Gigabyte GA-MA78G-DS3HAMD2+/AM2 AMD 780G HDMI ATX AMN,,,,,Hard drive----SEAGATE Barracuda 7200.10 ST3250410AS 250gb 7200rpm 16mg cache sata3.0b/s,,,,,, ONLITE DVD BURNER,,,,GSKILL HK 4gb (2x2GB),,,,,AMD 5000 Athalon 64x2 5000 2.6ghz socket AM265w Dual core ,,,, Raidmax Scorpion case comes with a 420 power supply in it .. .. I'm not installing any video cards in it yet as the person doesnt know whether or not they want one yet . I know that if they should want one in the future , or two installed ,,they'll need a larger PSU for sure ... Any help in insureing me this is ok to let go of the way she sets would be appreciated ...