So 4K60p is new. I was just doing 4K30p. I film outdoor video for YouTube, hiking and hoped that upping it to 60p would help bring out the detail. I can take it back down to 30p on 4K which worked well during edit. But I'd still like to be able to make something out of a 2 or 3 videos I shot in 4k60p if possible. It would export at 60p.

I read about the proxy. I've never done it so I am unsure on what to do exactly. Maybe I need to watch a video haha

Nothing is online so I couldn't send the link, sorry.

60p doesn't give additional detail but it changes the nature of how motion is perceived. It makes things smoother (can be an almost hyper-real video look). Traditional film is 24p which is relatively choppy but also abstracted from reality a bit which people perceive as "cinematic." 30p for NTSC is how TV looks.

So if you take your 60p footage on a 24p or 30p timeline and right-click and "add at project frame rate" you'll have 2x slow motion. Perfect for slowing down a moment of action, reveal of a scene, etc. You can add a velocity envelop to go between slow motion and regular time. In this way your 60p footage is more flexible than the 30p one.

If you just want to output it at 60p you are back to just real-time.

For proxy file it just makes a 720p easy to digest file for Vegas to read. When you render it still works with the original so nothing is lost. Go back to project media, right click and "create video proxy." Vegas will do the rest. When you go to say preview/auto or preview/full you'll see the proxy and hopefully get smooth playback. When you go to best/full you'll see the original file again (with choppy playback.)

If you want me to test a file just take your GoPro with your 60p settings, film a 10. sec clip of your cat or walking around the house and make it available via Google Drive, Dropbox, Box, OneDrive or some other service. The only point of this is to see if there's something about your settings that are worse than they should be for a system of these specs. I have both 15 and 18 installed here.

So 4K60p is new. I was just doing 4K30p. I film outdoor video for YouTube, hiking and hoped that upping it to 60p would help bring out the detail. I can take it back down to 30p on 4K which worked well during edit. But I'd still like to be able to make something out of a 2 or 3 videos I shot in 4k60p if possible. It would export at 60p.

With your CPU alone you could not expect to playback HEVC 4K60 smoothly, but with your cpu's IGPU decoder or Nvidia 1050 GPU decoder you should expect to play back fine. Vegas does not work well with 60fps, another user suggested a coding error causing the GPU decoder to overload, there was a recent thread about this that I added to.

Try the proxy option, most likely nothing you can do to make original files play smoothly