What other upgradeable components does the Dell OptiPlex 5060 SFF have?

Beyond the CPU and RAM, the OptiPlex 5060 SFF has an M.2 2230 slot for a Wi-Fi or Bluetooth card and a full-height PCIe x1 slot for expansion cards like a sound card, extra USB ports, or a network card. The SFF chassis gives you more room to play with than a mini PC would.