The best first option is to make sure you have the latest video drivers. Next make sure you have room on your drive for the data. If that doesn't help, then try redownloading NMS and reinstall.

I was having issues loading any save yesterday where it would crash to desktop as soon as I picked the save game to load. I tried a couple things, but what ended up working was opening the GOG Galaxy client, going to No Man's Sky, and clicking More > Manage Installation > Verify / Repair... I figured out was going to go out and download the full 10+ GBs of installers and all that, but it ended up only being like 700 MBs, so not nearly as bad as I expected. Once that completed (took ~10 minutes on my slow internet connection), I restarted my computer and ran NMS, and it booted right up where I'd left off on my saves without any further issues.