upgrading from i5 2300, used i7 2600, used i5 3570k or used i7 3770 worth it?

[superhiperpolulo]

hello I am mostly using my pc for games and I've noticed lower performance than expected in games such as BF4 and GTA:V (Which I've been told are CPU intensive) my current build is this: http://pcpartpicker.com/user/superhiperpolulo/saved/TJ2CmG

to try and improve my performance I am willing to upgrade my CPU (i5 2300) to a higher end model from the same socket since I don't want and can't afford a MOBO + RAM upgrade if I go for the Skylake route, I am also willing to sell my current CPU for around $60 to make the upgrade cost less

As of now I've found some used i7 deals that I am asking which would be the better option?:
-i7 2600 or i5 3570k for $120
or
-i7 3770 for $170

also will that improve my performance in games from my actual i5 2300 to be worth it or should I be looking for a new, current gen processor for that?

 

[dudeman509]

Go for the 3770.

Yes, single-threaded and multi-core performance is quite a bit better than the 2300.

 

[superhiperpolulo]

Go for the 3770.

Yes, single-threaded and multi-core performance is quite a bit better than the 2300.

Fine but ill wait for more opinions.

 

[superhiperpolulo]

Edit: I've also found i5 3570k for the same price as the 2600.

 

[Rogurzz]

Edit: I've also found i5 3570k for the same price as the 2600.

Get the 3770. Still really fast and won't bottleneck any GPU. This CPU will last 2+ years.

I have the CPU, it handles ANY game you throw at it.