Second Personal Computer

I am using a dynabook N40 with Ubuntu installed, but it freezes frequently, so I am considering buying a second computer. I think that one of the deciding points for a home computer was whether or not it could smoothly watch videos such as Youtube and Netflix a long time ago, but nowadays I think that such videos can be watched on FireTV, etc., I am using it with my REGZA’s HDMI and I watch it when I get tired of my Dynabook. The purposes of my home PC, excluding video viewing, can be generally categorized into the following, unless it is also used for work.

1. game-related
2. video editing
3. investing in stocks, cryptocurrencies, etc.
4. surfing the Internet (archaic word?).
5. others

I guess it’s like that. In my case, it is “5. others” + “Linux-install-hollic” (archaic word? lol) . Therefore, I do not need a high-spec CPU, and then I am considering a mini PC or a stick PC about the same size as a FireTV.