i have the lenovo z5075
all the games that i have played while using the amd dual graphics (apu+deticated) suffers from severe sluttering and low lag (4 to 5 fps) at any settings.
the dual graphics is a combo of the fx 7500 apu with a amd radeon r5 m230 and this is called r7m260dx in the device manager.
while playing i have tried monitering the r7 m260dx with gpuz and it only runs at 200mhz
but it should be able to run at 855mhz gpu clock
i have also tried using the whql drivers from the amd site but it makes no difference.