HP EliteDesk 800 G1 Mini — 4th Gen Haswell, socketed and upgradeable

The EliteDesk 800 G1 Mini uses an LGA 1150 socket supporting 4th Gen Intel Core processors (Haswell) — i3, i5, or i7 at 35W or 65W TDP. It’s an older platform now, but the CPU is socketed and replaceable, which is rare in a mini PC.