For some time, Fortnite has had a habit of closing after a few minutes of play, sometimes as early as the first game and sometimes after 2/3. Now this extends to Warzone too.
The error messages are no help to be honest, no error codes, nothing. I suspect it might be the graphics card, but I don’t know how to confirm that either. I have an Nvidia GeForce RTX 2070 Super.
Edit: Problem solved, thanks to @pezmaker@sh.itjust.works, it was the RAM, twice already that Amazon delivers me a defective one. I’ve put the old one back in and no more problems.
To stress-test your gpu you can use Furmark. https://www.techpowerup.com/download/furmark/
Simply download it, install and launch it and crank the settings up nice and high.
Leave it run for an hour orso, and if Furmark crashes then your gpu is probably toast.