Comment by sfink
From someone who ships software that runs on hundreds of millions of computers: please consider running a memory tester once in a while, particularly if you have any unexplained crashes. The days of being able to assume "it's not the hardware, stupid" are past. Bit flips can and do happen. We've made everything small, fast, and cheap. Those are great attributes, but they come with a cost: we've also made things hot and unstable and removed all the safety margins that were in the way.
But also note that a memory test passing doesn't mean the ram (or CPU) is fine.
I overclocked my system for fun and for ram you'd run 2-3 different tests to be able to call it stable with some confidence, as they all have different access patterns and r/w ratios.
Memtest86/+ are usually seen as worse compared to the other tests like say or karhu ram test or testme5, but those also need an OS to run and in the rare chance only some region of memory is faulty could miss it