Well, I have a notebook that's a few years old, but I'm still happy with it… It could have a better CPU, that's all.
I'm just wondering if I buy as a second device, a new, more modern notebook or directly a desktop PC, because there you get more for your money.
If I want to be mobile, I would still have my older laptop. What would you do? 2 laptops or 1 old laptop + 1 tower
With the laptop you can just go to bed or on the couch. The desktop would have the better graphics. For that you have to sit in the chair. For 600 euro n laptop unique
If you are also interested in current games it is definitely a desktop / tower that is a must. Notebooks that can handle the latest graphics-heavy games are damned expensive and you may still have problems with some games.
If your notebook is still serving you well and you only find the CPU weak, you could of course go to a PC dealer and have the CPU replaced with the best CPU for the motherboard.
If games are of no importance to you, a new laptop is probably better for you. But if the old one still does it, I would not pick a new one but wait for a while. Then the new purchase is worth more.