Impossibly poor performance editing 4K

[SteveMartinUSA]

I find VideoStudio 2020 "ultimate" starts to get unusable after Full HD resolutions. I haven't found a way to edit 4K video in VideoStudio 2020, even from a very capable laptop. Scrubbing across a 4k source clip with VS 2020 is a total failure, and that's a big bummer.

I've had unpredictable results with "smart proxy". For example, I only see a few of the proxy files created. Do you have to re-add a clip to the timeline to get a smart proxy file to create? When VS does start to create a proxy the CPU can go to 80%-90% range for a couple minutes while it proxies just the one file. The proxy file has a "UPX" extension. It's not an MP4, so I can't tell if the file is just for the trim on the timeline or for the whole file. Does VS have to rebuild the proxy if I adjust the trim.....?

My testing is a six minute long video from 4k 30 and 60 fps source clips. And all of this testing is done from my XPS 9500, with an i7 10875 processor and an NVidia 1650 GPU, and SSD storage (9/13/2020). I've tried both hardware compressions (Intel & NVidia, with a restart between selections) and watch the CPU come close to 100% while the video tries to play but really jerks around like an epileptic.

Where VideoStudio bombs, I have a smooth experience with Filmora on Windows or Lumafusion on an iPad Air 3. I don't have to generate a proxy in either of those--I'm able to work with the full resolution videos on the timeline and can scrub smoothly.

[Choi seong chul]

I have no problem with 4K editing. Create a smart proxy file
You can select all and create a smart proxy file.

[Ken Berry]

Steve -- you've already posted this in another thread. I am going to lock this to avoid confusion. Please continue discussion in the other thread: https://forum.corel.com/viewtopic.php?p=381461#p381461