Does anyone know the speed increase or advantage of a dual core pentium (pentium D) over a single core Pentium 4? I've heard about lack of software optimization for the dual core leading to lower than expected gains (whatever that means.) Also, can someone tell me what PC graphics card I should be looking for these days? The last time I checked, the Radeon 9800pro was tops. Things change so quickly. How about a Geforce 6600? This computer's main purpose will be gaming (I'm a resolution and frame rate whore!), video editing, and watching/recording TV. Thanks!