Intel i3 1155 2nd Gen

Hi everybody i'm new to the site, been watching the vids on YT a long time though.

I'm still trying to upgrade my PC(slowly goes) but I cant decide what my next CPU should be...

I love to game. I'm an FPS fan boy(bf3, planetside 2, blacklight, metro, etc...).

I dont have much money as i'm only 16 and spend most my time at school.

I was just wondering should I spend my saved up money on a  £90 Intel i3 2nd gen(yes I am British and I do like tea and cricket).

Or mabye should I save up abit more and buy the i5 about £150($228). Whats the difference in performance?

Will most games today or in the next year or 2 take advantage of more cores. Is it worth the money?

My current PC specs are: 

Intel Pentium G860 3.0Ghz

8gb Crucial Ballistix Tactical DDR3 1333Mhz

AMD Radeon HD 7770 1GB XFX CO

500gb 7200rpm Drive

EvoLabs 750w psu

AsRock H61M-VS Motherboard

Love you Logan(completely straight).

Someone reply!

Your computer build right now is pretty decent you should be able to play those games at decent settings and FPS