  You havent said why you want faster graphics. Games? If so, you need a new machine. For pro apps though, you should be just fine, unless you are using Motion, then you still need a new machine. You wont get much faster unless you go with a MDD or G0 and for the bucks, I say go with mactel. That said, you have a very fine machine.  The QS board will not fit without some mods and to be honest, it is on the whole, cheaper to buy the whole machine as they are going for around 000 bucks right now.  