Why is it in Fortnite?

I have the following problem, and Fortnite lies with me every 10 seconds and my 144 FPS then go down to 50 FPS, which is abnormally disturbing.

I bought a LAN cable and every game runs perfectly, except Fortnite…

My ping is always ~ 20

So it's probably not because of my internet…

My PC specs are:

i7-9700F and GTX 1660 Ti

The lan cable is of no use for the fps

If I had one, reinstall the game

Maybe a driver is missing?

I always used to have 60-100 FPS in Battlefront, since I have a LAN cable it has been running constantly at 100 FPS

Maybe you haven't downloaded all the drivers

Jo, where can I see?

So I updated the graphics card driver on the Nvidia page