Cpu upgrade??

i have a computer with 2 gb ram and a gf7600gs 512mb and my cpu is p4 3.2ghz, and i'm going to change my cpu to core 2 duo 2.0 ghz and i wonder how much difference there will be between those cpu's in this computer, a lot of difference or not so much?? thanksCpu upgrade??core2duo rocks. I used to be totally AMD .. but since using the core2, I won't go anywhere near AMD anymore, the earlier Intel CPUs are ok, but the newer core2 you will find much more efficient.Cpu upgrade??first question is. Does the mainboard support dual core?