Hi, the best deal on processors is the Intel Core i5 2500K, if you want the same performance and you don't want to spend much, the AMD Phenom 2 X6 1100T is the best option, but you have to search a motherboard compatible with those processors, and the RAM, the RAM for the AMD must run at 1333MHz, and for the Intel is 1066MHz and 1333MHz, just find motherboards compatible with those processors, the retail stores can help you and that, and the video cards, I recomend the ATI video cards, they are more cheaper than Nvdia and more versatile, I recomend the 6870. 6950 or the 6970. If you want for example more than 4gb of RAM you must buy Windows 7 64bits.