Aurora slugish sometimes

Sometimes on booting Aurora and starting to browse and other tasks, the system becomes unresponsive as in very slow. Only a reboot fixes it. I was thinking that it might have to do with the downloads on the background of updates as my wifi connection at home is slow.

What is the best way to diagnose what the reason is? I previously used Linux Mint on this laptop (Dell XPS 9300) without an issue apart from overheating but that is linked to the thermal paste or too thin case body of these XPS laptops.