Before I got into the home server ecosystem, I’d only use PCIe slots to pair graphics cards to my gaming rigs and then forget about them altogether until my next PC building misadventure. But little did I know that every unoccupied PCIe slot was a free expansion header that’s as useful for home lab nodes as it is for an everyday machine. With all kinds of adapters floating out there, slotting one into a spare PCIe socket can add extra functionality to budget-friendly motherboards.