Mini PCs from brands like Geekom, Beelink and Minisforum offer desktop-class performance in a tiny footprint, but their size creates significant trade-offs. Upgradability is severely limited — CPUs and GPUs are typically soldered to the motherboard, leaving only RAM and SSD slots (often SO-DIMM and M.2) as potential upgrade paths, if they aren't also soldered. Expansion options are scarce due to cramped internals and fewer USB ports, though some mid-tier models include OCuLink or Thunderbolt for external GPU enclosures.

Cooling is the fundamental constraint. With minimal space for airflow, mini PCs cannot dissipate heat like full-size desktops. Even high-end models using chips like the AMD Ryzen AI Max+ 395 — which rivals the desktop AMD Ryzen 9 9950X — run hot and loud under sustained loads. Traditional liquid cooling isn't practical. This thermal ceiling caps sustained performance, making mini PCs unsuitable for prolonged heavy workloads compared to larger desktops with robust air or liquid cooling.