The GPU part of the 7850K is near enough on par with 7750.
The 7750 does have the advantage of using GDDR5 memory, while the A10 has to share the DDR3 main memory and performs best with memory speeds of DDR3-1866 or DDR3-2133.
So the A10-7850K is ok for light gaming, if you need more, go with a cpu+gpu combination.