I had bad RAM on my primary Linux desktop some ~six years ago and it caused an endless series of problems, data corruption, and hard reboots every few months. It happened so infrequently that I never quite tracked it down, but I'd copied hundreds of gigabytes of data between computers over my LAN and lots of random files still have some corrupted bits in them to this day from that.

I finally got serious about tracking down the issue, ran memtest, and sure enough, it discovered a faulty DIMM pretty quickly. I yanked it out and the problems immediately went away.