i have acer nitro 5 an515-43 ryzen variant and no games are working its stuttering every second

i have acer nitro 5 an515-43. it has amd ryzen 3550h processor with integrated vega 8 graphics and amd radeon rx560x 4gb gpu.. and 8 gb of ram in which 2.1 gb is reserved by vega 8 graphics so i only have 5.9 gb usable.. and now my problem is whenever i start a game just after 2 min games starts stuttering very worse like from 60 - 70 fps it drops down to 10-15 fps and its happening in every game like gta 5, rogue company, fortnite, far cry 3 and many more. i've tried everything like lowering down the settings in every game stoping background apps in win10 but nothing worked even i've gone to service centre they said that the gpu in onboard and the problem is in gpu thus they changed my motherboard with a new one but even after this nothing changed and still i have the same issue please help me... no games are playable after 2 mins of startiing any games it starts stuttering like worse and after that it happens every few seconds and the frame drops from 60-70 to 10-15.. i'm very frustrated i'm feeling like i wasted my money on this laptop.. please someone help me please..

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AnhEZ28

When the game starts, what is your temperature of both CPU and GPU at that point?

Tushar784264

AnhEZ28 said:

When the game starts, what is your temperature of both CPU and GPU at that point?

temperatures starts with like 50-60 degree celcius and starts rising after the game loads and after few mins it constantly be within 85 to 90 degree celcius for the whole time.. but as i have got my motherboard changed 5 days ago so i think the pasting over the gpu and cpu were also changed so what to do now.. please help