My laptop is underperforming

[burninglion22]

Hello, my laptop is underperforming,the gaming performance is pretty bad......
I bought this laptop on christmas to play games on it but it isnt working right nowadays before i got this problem i had about 150-200 fps on low settings 1080p and everything was ok but about sometime ago it started getting worse,at the point i am at i have 80 fps on 480p lowest settings and many games work different how they're supposed to work.I bought this laptop because of a review i randomly found online and the reviewer said that as long as i dont go above medium settings everything should work fine so i was ok with that and bought this laptop for about 450 euros.
I want to try and fix this and as a last resort i am going to send it to warranty,and a friend also has this problem on his laptop.
The laptop's specs are:
RX540
amd a12 9720p
4gb ram
ssd
hdd
And that's about it,and also i know that the cpu is pretty weak.

 

[rgd1101]

MERGED QUESTION
Question from burninglion22 : "I have a problem with my laptop"

Hello,so i bought a laptop when it was christmas because my pc was pretty bad but the gaming performance is bad,and its not supposed to be like this...
I read a review about the laptop and the guy said that i could play with medium-high settings in some pretty new games,and i also read some reviews on the site and they said that the performance is just like the reviewer said, but i dont really understand how it works worse than what they said ,and i dont know whats wrong...After about 1 week i have to reset it because the performance gets worse overtime,i tested gta 5 and i had the same fps as my integrated even though the dedicated gpu was used

Specs:
RX 540 2G
4 GB RAM 931 Mhz
AMD A12 9720P
231 GB SSD
Integrated:
R7 Graphics