I have a standard PC I got from Best Buy and the graphic card is intergrated or whatever the term is where its attached to the motherboard. My question is can I replace it to upgrade it or do I have to buy a whole new PC to upgrade my graphic card? The reason I'm asking is because my graphics card is really outdated and I and having problems playing anything other than WOW on it now & my fps drops down to single digits on a couple AOE heavy fights in 25 man.