I am putting some parts together for a friend and the power supply he gave me is too small for the mother board power. It leaves 4 slots left unused. Does he need a brand new power supply or what?
I assume your power supply has 20 pins and your motherboard has a 24-pin plug. (Some power supplies have an additional +4 pin connector that attaches to the side of the 20 pin connector.)
If you don't have that +4 connector you need a new power supply.