thought it would be better

I recently brought a new pc, I have been wanting one for ages and haven't had the money. However Argos gave me the opportunity to pay the £500 over a year period with a special 0% interest card. I would have prefer to build my own but I'm terrible at saving so the card really helped me. I looked at the specs and thought for the money I'm paying surely I'm gonna get decent fps.

The specs are
CPU and Memory:

• AMD A10 quad core.
• A10-7850k.
• Processor speed 3.7GHz.

DVD optical drives:

• Dual layer.

Graphics:

• Shared graphics.
• AMD Radeon HD .

The only games I play are league of legends and occasionally CSGO. On high setting I was getting around 42 fps on league and in team fights dropping to 25. As well as that when changing the graphic setting ( eg medium low very low) the fps doesn't change it stays between the 40-50 mark. I wasn't expecting when buying the pc to have 200+ fps but I thought it would be better than that. I use to play on a ****ty i3 laptop that had similar fps to that so you can see my disappoint when I will be spending £500 for this. I just wanna know if there is any point in me keeping this or is there something that is wrong. I just want a bit of help cause I don't quite understand why its performing so poorly?