acer aspire E-1 572G problem with the hd 8750m gpu

hello,

i can't make games use the hd 8750m's gpu i tried installing pilotes from several sites i used the autodetectutility from amd site i tried the intel integrated from the device manager and the screen resolution reduced to 800x600

please i need real working solution to this i don't need answers like install another driver etc ..
sorry for my bad english