Zend certified PHP/Magento developer

games running on lower fps than expected

so i have a little problem. I have a nice pc with a new rtx 4070 and a ryzen 7 3700x. I have 32 gb of ram and a b450 tomahawk max 2 as a motherboard. So before the 4070 i had a 1660 ti. On games like fortnite i used to run around 200 fps on low settings wich is ok. Now that i upgraded to a 4070 i run exactly the same. i see people getting like a 1000 fps while i cant even go past 250, which is very dissapointing because i have a monitor with 240hz.

Can anyone please find me a solution?
thanks!