Well since you never said how much you're willing to spend, it'll be a bit useless for me to go into all that. I will say this though, Assassin's Creed isn't that big of a deal, but Crysis on full will bring a lot of pcs to their knees, so buying a machine off the shelf that can handle it will cost a pretty penny. Quadros aren't gaming cards, they're workstation cards. A good gaming card(s) will do fine, you can look into the Nvidia GeForce 9 series. Either start reading up on this stuff or call a buddy who can build pcs or you're going to have to shell out a lot of cash for an off the rack affair. As far as the processor, if you multi-task, get a quad core, if you don't multi-task, get a dual core will a high frequency.