Why isn't my Dedicated Graphics card being utilized?

I have a Lenovo G510 with Intel Core i7-4702MQ @ 2.20GHz, 8GB DDR3 Ram, and Intel Integrated graphics 4600 with 2gb vram as well as an AMD Radeon HD 8600/8700 chipset with 2gb vram as well. I think my AMD is an AMD Radeon HD 8750m to be exact. I went on amd catalyst control center and set the graphics settings of just cause 2 to high performance and when I ran the benchmark on Just Cause 2 it gave me an average fps of 28 and it told me that it used Intel Integrated Graphics 4600… Why can't I get my amd card to work?!

Laptop dedicated graphic cards take more power and cooling. Have to use plug in adapter instead of battery on some laptops.
Game settings can be another factor. If exists, you can do it in there.