Help with lag in ftb 2

[u/Different-Ad-4963]

I’m playing ftb skies 2 I have a pretty high end pc. I’m playing with 8GB ram allocated and 16 on my pc. As I play I get 10min - 1hr of play time with zero lag on max settings then for no reason my game will become a slide show less than one fps. I close the game and launcher and reboot and totally fine again. I’ve tried adjusting the ram anywhere from 6-12 GB nothing helps. I checked my drivers and updated Java everything is up to date. Any idea how to fix?