Intel iris xe freeze

Hi, so, was super excited to get a vostro 14, saw performance videos and was blown away but on getting mine, it's really not the case here.. 

Let me explain:

I noticed games and software lags for the first few minutes then becomes stable...

But in order cases, games open flawlessly but few minutes in, gets massive lags... 

My driver's are up to date, running Windows 11, I really don't know what the issues is, but other brands with the same configuration are working fine. So what could be the issue?