@WetGeek, it is a Lenovo Thinkcentre (not a Thinkpad) M700, a mini PC. It is a few years old, not terribly old.
I tried installing another OS because of the problems I mentioned in another topic, then switched back to Solus. I can't remember that I would change anything significant in the process.
@EbonJaeger, thanks for the link, I should go through it. At first glance, I don't see that any of these advice would help. Also, I tried reinstalling Solus a few times, first encrypted as I usually do, then without encryption. No special partitioning was used, I just installed it on the SSD drive.