Everything except the gpu. If you don't game at all, look into a professional workstation card like Quadro FX or FireGL, whichever is supported by all the software you run. These expensive cards are designed for 3d rendering. ebay has some of them for cheap.
Sorry, I totally missed gaming in your post. Go with HD4870. Yes, it will be slower than Quadro in 3d rendering, but I don't think you're staring at the computer while it's rendering which may take hours or even days. When you game, you want optimal performance.