Can I run a node on an old laptop or my home computer?

Yes you can but you need to understand that more node rewards will be distributed to nodes that have high availability (always on) and a fast internet connection. If you’re running a janky old laptop that swaps memory everytime it gets a request your quality ranking will be low and you’ll make fewer Presearch rewards.
I would recommend getting a Low Cost Mini PC or a Raspberry Pi 4B with at least 4GB ram kit from Amazon and just let it run sitting on the corner of your desk.

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