I purchased parts for a new computer off Newegg a few days ago but before they arrive, I'd like more opinions on it. While those on other forums were helpful in selecting the parts, few overall actually commented on the build itself. The main reason I'm posting this is to see where any possible weak points could be for future upgrades. I'm thinking I could have saved myself about $40 if I went with a 550 W Power Supply but I wasn't sure if that would be enough in the future.
I understand the motherboard only has one PCIe x16 slot; I don't really care for SLI and that was the cheapest motherboard I could find that supported the Core i5 Processor. Also, I went with the i5 since I don't see myself taking advantage of the hyperthreading the Core i7s provide to warrant the extra cost. This cost me about $860 shipping and all but, I'm selling my current rig for about $400 to a friend of mine to help out with the overall cost.

P.S: What can you use a PCI x4 slot for? I think the GPU might cover it up but if not, what could I put in there (Not that I would)?