I did a little more research and found this which is pretty helpful:
http://www.tomshardware.com/2006/07/..._64/index.html
From all the benchmarks the core 2 duo blows away all of AMD's processors. There werent any benchmarks for the e6400...but do you guys think the e6400 could outperform a x2 4600(or 4800), since they're about in the same price range. Also, yes I do have money for a new motherboard.