The other one was very very underpowered so I threw CasaOS onto it

How did you get past the website? It's bloody awful :o

Joking aside though, I hadn't heard of CasaOS, so I just did a quick search. That website is awful on mobile. I swiped up, assuming that there was more than just the live demo link, but nothing happened for a while. Then, loads of content popped up at once and scrolled past >.<

I've sent it to myself to check out on the computer. Hopefully, if it does what it claims, it could resurrect an old laptop :)