Yes, actually. At some point when I was trying to get the linux install going, it was not booting due to a fan error. I did my best to take apart what I could and blow out some dust. Again, hardware is not my thing, so I was never able to take the case apart completely, so there could still be dust in there.
It could be hardware failure. With just 4 GB RAM, you're asking a lot from your old HDD. I recently saw a case in which an
incorrect CPU voltage setting caused problems syncing.
So that's why Bitcoin Core gives a warning when started for the first time:
This initial synchronisation is very demanding, and may expose hardware problems with your computer that had previously gone unnoticed.
Memtest won't expose all possible problems.
Any chance the laptop cooling system is filled with dust?