Thanks. I would rather have an i7 than an i5 though. Could you tell me why this is better, for gaming or other business? I got the case and power supply already covered so don't worry about that. Oh and 3,5g or more paste suggested?
PS: Sorry for voting down your answer, happened accidentally.
3.5G of paste should be enough (one application of thermal paste should be roughly 1 gram, hence 3.5 should last for 3 uses).
As for i7 vs i5, it's very simple really. i7 CPUs are simply more powerful than their i5 equivalents. For gaming this makes little difference (with the notable exception of simulation-heavy games like Cities: Skylines and Total War games, although you'll likely not encounter any problems with a high-end i5). For non-gaming applications like video editing or 3D design the i7 CPUs are better because they have Hyperthreading, which is essentially useless for games but allows such applications to better utilize the CPU.
Overall, spending the extra money on an i7 and cutting down elsewhere is simply NOT worth it for gaming. Especially getting a K-series i5 (e.g. i5 4690k) is a much better choice than a non-K i7 because it is much less expensive and allows you to overclock it if and when it becomes insufficient. Also you can put the saved money into a better GPU/motherboard/SSD.