ACER ASPIRE ES-551G-T6Q7 Dual Graphic Problem

Hello,i recently bought a ACER ASPIRE ES-551G-T6Q7 with Integrated AMD Radeon R6 Graphic card and a Dedicated AMD Radeon R7 M265 Graphic card and I can notuseinany way Dedicated R7 Graphic Card,i have installed latest drivers and set everything to High Performance bun games like GTA V or GTA IV using only integrated graphics,
that wouldbethe solution to play games uning dedicated R7 Graphics Card?