Will this PC bottleneck a single radeon 4870 single core or x2? Do I absolutely have to have a Core i7 965 OC'ed to 4.0 GHz with 12 GB DDR3 RAM to fully handle it's throughput? Is there any way I could upgrade the processor? I noticed that the power supply is very low for a system with these specs, if I were to upgrade, what wattage would you recommend? Could you perhaps give me some recommendations and link them to me on newegg? It took me 5 months to convince my stepfather to buy this computer, he originally wanted to buy some $400 piece of crap HP workstation.

I would have liked a PC with better specs, but he wouldn't budge.

Here is a link to the specs.