For the processor, you should get the Q6600 Energy Efficient version (G0 stepping) which has a better performance than the standard one and is easier to overclock. Memory wise, you should get some OCZ RAM instead of Corsair because it is much better value for money, and has very similar performance to Corsair. This is the RAM that I am planning to get for my new PC - although you may find it too expensive. In terms of graphics, you would really notice the difference if you could get an 8800GTS but I understand if that is out of your price range. The PSU sounds fine although you couldn't go wrong with a 600W PSU which would give you extra room to change your setup. I recommend using the Intel P35 chipset for overclocking, although if you want SLi you should get the 680i chipset from Nvidia. I prefer Asus motherboards over other manufacturers although it is your choice. If you are building a new PC from scratch, then you also need to think about your operating system, case, sound card (built in is usually crap), CD/DVD drive and hard drive for which I recommend this (I will be getting this for my new PC). I hope this helps, let me know if you have any more questions.