What Kind Of MotherBoard Does a Dell Dimension 4600 Have?

You talking about a processor or a mother board?Micro ATX , Mid tower (i) or slim (c)? ATX boards generally average 12" long X 9.5". Micro ATX boards are in the area of 9.5"X 9.5". The full size board will not fit in a "i" case. The power source for a 4600i is standard ATX. I have never seen a "c". A little proof reading on you part would help to answer you question better.