For all the I/O bottlenecks it has, I've still been rather surprised at the Pi 4/400's raw number-crunching power. It compares well to a 3.3 GHz i3-2120 in a clustered number-crunching task I sometimes run (via MPICH) - which seriously surprised me. I suspect that if it were too big to fit in-cache, the Pi would probably fall flat on its face, but still it just floors me that this itsy-bitsy SoC can do so much on seven watts at the wall socket.