No amd has no chance to bring gddr5
Haswell-e would bring gddr4
THE APU NEEDS A FASTER RAM RATHER THAN MORE RAM
The best u can do is get a 8gb(2x4gb) 2133mhz or higher clocked ram
as it would b required by the integrated gpu which would be better if u get more clocked speeds
Memory: G.Skill Ripjaws Z Series 8GB (2 x 4GB) DDR3-2400 Memory ($79.99 @ Newegg)