I'm looking to buy an ethernet card for my Pentium 4 PC and am wondering if they all are basically the same. There are two computers in my house (an IMAC and my PC) and both will be using the same cable internet connection via a hub. Is there a special card that I should use? I know I need a hub and RJ 45 cable but am unsure about the card for my PC. The Apple already has a card.