Written 25 Aug 2026. This is a how-to, not a product card. Buy links are not tagged yet.

Don't cook the leftover box

The leftover box stays on. It needs air. A laptop under a pile of clothes will cook. Skip this if the leftover is a desktop with vents clear.

The leftover box stays on. It needs air. A leftover laptop shoved under a desk, lid shut, sweater on top, will cook. Then it throttles: it slows itself down to stay alive. Then SSH and Pi-hole drop. The box is not off. It is too hot to keep working.

Skip this if the leftover is a desktop

A leftover OptiPlex, EliteDesk, or mini PC sitting on a hard surface, with vents clear, already has air. Skip this note. Come back only if you boxed it in a closed cabinet, or covered the vents.

A laptop still needs a hard, open surface

The lid can be shut. That is don't let the leftover laptop sleep. Give the leftover laptop a hard, open surface. A desk, a shelf, a book. Not carpet. Not a sofa. Not inside a closed cabinet. Air has to leave the vents. The sleep note already says do not bury it under a sweater. This is the rest of that job: air, dust, and the difference between warm and hot.

Warm is fine. Hot is not.

Warm is fine. Hot means you cannot keep a hand on the metal for a few seconds. If you cannot, move it. Give it more air. No thermometer required.

Dust, once

Once, blow the vents. Do not vacuum the fan. A vacuum can spin the fan too fast and break it. You do not need a command. If you want to see that the leftover box has been on, this is optional:

uptime

That is look, then maybe type. Most of this note is look. Do not type.

What next

If the leftover is a laptop, keep it awake when the lid closes. That is don't let the leftover laptop sleep. If you are done for the night, shut down the leftover box without yanking the plug. If ads came back this morning, or SSH hangs, that is is the leftover box still on?. Do not buy a rack. Do not buy a NAS.

Skip

Skip this note if the leftover is a desktop or a mini PC on a shelf with vents clear. Skip a cooling pad, a new case, and a rack this pass.

Sources

Debian: uptime. Ubuntu: uptime. Official pages only. For the leftover box, see start with what you already have. For the lid, see don't let the leftover laptop sleep. For the night, see shut down the leftover box without yanking the plug.

Also on this topic

Don't let the leftover laptop sleepClose the lid. The leftover laptop has to stay awake so SSH and Pi-hole keep working. A leftover desktop can skip this note. Shut down the leftover box without yanking the plugWhen you are done for the night, tell the leftover box to finish writing, then power off. Do not yank the cord. Skip this if you only need a reboot after updates. Start with what you already haveDo not buy anything yet. Old laptop first, or a retired OptiPlex from Marketplace.