I'm really bad with graphics cards, but i got this game and the minimum graphics card I should have in my PC is NVIDIA GeForce 6600 GT/ATI Radeon X 1600 or higher, currently my graphics card is Mobile Intel (R) 4 Series Express Chipset Family, Is my current graphics card lower than the minumum graphics card required and if so, how much would it cost for a newer graphics card, like one of the graphics cards I listed above, and is it even possible to replace a graphics card? (I'm really bad with graphics cards)