Add memory, get FPS boost?

Tradesman1

Legenda in Aeternum
Are you using the APUs iGPU? If so go to 8GB should give a healthy boost, as right now a portion of DRAM is dedicated to the iGPU so processing of data for the game or whatever has a limited amount of DRAM. Upgrading to 8GB will provide more for your overall system and also maybe more to the iGPU which would be an additional performance burst
 
It depends what ram you're currently running ???

2x4gb 1866 sticks in dual channel mode should give decent performance.

What would really make a difference is an aftermarket cooler & overclocking the GPU portion of the chip if your motherboard is up to the job.
You can push a 30-40% fps increase this way.