So my graphics card died

How did your gpu die? I had problems with my GTX460 a few weeks ago, but it was caused just by the new driver. The computer was randomly freezing and shutting down. But after switching to the older 314 driver, everything works now.

Anyway, if you want the physx, just stick to the nVidia. Although the AMD has great gpus now, especially if you're going to overclock them. But I'd go with nVidia as well, I love the physx :3

Cooling - the back exhaust system doesn't work that well, it's usually quite loud and run hot anyway. I'd go with other 3rd party cooling solutions, eventho you don't have much space in the case. The Asus has great cooler, they're quite expensive tho. The MSI Hawk is pretty good cooler as well, reasonably priced, but a bit louder in idle and the fans are quite cheap (might get louder later). If you can pick up the Gigabyte one (with the blue pcb, it's not available everywhere), that'd be great solution as well. The cooler is good enough, but most of all, it's priced same as the graphic cards with reference coolers.

GTX 660 is ok

nVidia 4 life, thug life bro, swag yolo

No need to get anything over a GTX 660 as your CPU is going to start bottlenecking after that. I'd only go AMD if they still have a game pack going that you might be interested in. Otherwise it's just worth it to get Nvidia for less hassle, particularly for Physx, which yes you can enable on your CPU in some games but still a hassle.

There really is no difference between AMD and Nvidia that a driver update doesn't fix within a month for equal hardware so you can't really go wrong. If you don't mind paying a premium nothing wrong with going with Nvidia, since they also resell better too.

Did you try baking? 420 yolo swag

Oh, sorry to hear that.