ok so i currently have a G5 PPC mac with 2, 2GHz cpu's and i was thinking of upgrading to one of the new iMacs, the one i am looking at is 3.06 GHz, which one would be faster? and i know that just looking at that you would think ohh four GHz vs 3.06 GHz easy the 4, but wouldnt the newer one be faster than the 6 year old one?