Comment by account42

> To this day, what surprises me most is that my computer was able to successfully boot and behave normally for an hour or two, even though random bits were apparently being flipped.

With my current computer I overclocked the RAM to the best config I could get memtest to run without errors over the night. The RAM also has ECC and there were no problems reported during normal operation, even when re-compiling (most) packages. But when I got to compiling LLVM the system would crash shortly after logging ECC errors. Backing off the overclock a bit fixed that. So the rate of memory errors can definitely depend on what you are running.