Preview is choppy

Hello. I recently downloaded Resolve 15 and tried to edit some of the videos I shot using GoPro Hero 7. I shot them in 2.7k 60fps. When I import the medias to Resolve 15, the preview is really choppy so it's hard to edit. My desktop is i5 6500, 16GB RAM, RX580 8GB OC, and using two 32 inch 4k monitors plus one 1080p 24 inch. Is it my system that's slowing things down?

"Is it my system that's slowing things down?" Yes !

Your recordings are hard compressed - and it requires a powerful CPU !