Upgradation

Hello everyone! I hope you all are doing fine. Recently I faced a problem during editing my footages in DaVinci and Premiere pro. I shoot all my videos in 4k 10 bit from my v90 sd card. But after transferring it to my PC all the videos get lagged drastically and lagged way too much in DaVinci resolved itself after importing the videos in playback. It's stuck in from the beginning. My PC specs ... Amd Ryzen 5 3500 Motherboard gigabyte b450m GPU- GTX 1660 super I have no nmve ssd but a sata SSD and normal 1 tb harddrive RAM 16gb

What shall I update to resolve it?