Advice on upgrade

[rlcf101]

Hi guys

 

I need advice on upgrading my current system:

 

CPU: AMD A8 7600

MB: Asrock a88 itx

RAM: 2 X 4gb Gskill 2133mhz

GPU: Sapphire R9 380 itx 2gb

CASING: Silverstone Raven RVZ01

 

I gotten the A8 7600 as an entry level system and game abit on dota2 but later when the MGSV TPP came out, I added  the R9 380.

 

However I feel like my CPU is bottlenecking the system as I watched even the potato masher from casual shenanigans can get a constant 60fps, while I feel my system should be more powerful, but can only get 40-50fps with the same settings.

 

http://casualshenanigans.com/2015/09/22/metal-gear-solid-v-the-phantom-pain/

 

If I were to have a constant 60fps for MGSV, should I try upgrading to an Athlon 860x or should I just upgrade to an i3 6100 system for abit of future proofing?

 

Or should I just wait out till Zen and the new Intel architecture?

 

I reside in Singapore and have a budget of around USD300 for the upgrade. 

 

Thanks in advance!