I already replied once but I noticed something else You're ram could be better 2gig is ok but if you're motherboard can support it 8GB at 1016Mhz
Although with a GPU like you have you must be running DDR3 So RAM could be the same amount but at a faster clock speed
Try cclonline.com.
They have litterally loads to choose from.
Also the graphics card although the one you have is among the top of its range there are higher. 9800GT 1GB dedicated although that depends on how much money you have. I don't know again if you're board supports this as its highly exspensive but intels new chip the

intel core 2 duo extreme or something like that

I wanted one of these but the price kinda drives you away at 630 its exspensive. Thats if you're motherboard has 775 socket