So I was considering upgrading from my 2 year old MBP after upgrading from HDD to SSD and 4Gb RAM to 8GB RAM and realising that the biggest bottlenecks of the system were the only things you couldn't replace- the CPU and GPU. When comparing them to the rMBP, they look pathetic. So when looking at the Apple site, messing around with some configurations, it hit me that I didn't want to make the same mistake of getting the baseline MBP, because I will be using it as my main computer (Gaming, Word stuff, Windows etc). So if I were to go for the baseline, that would be the CPU I'd have to live with. As they don't offer different choices for the GPU, I can't stress that subject because there is nothing I can do. And I know that getting the 2.3GHz model means I am limited to 256GB space, that is sufficent enough for me, if need be, I'll use my current SSD as an external storage device. So the question is- What is the performance difference between the three CPU models (I know they are just speeds)? And which should I get, considering that my rMBP will be my main, and only computer? EDIT: I was just thinking, are the different speeds just different overclocks? If so, I can do that myself, right?