The Quiet £50 Node: Turning UK Surplus Mini PCs into a Proxmox Lab

Why surplus kit wins

A home lab is usually a compromise between curiosity and the electricity bill. The good news is that the UK surplus market is full of ex-corporate thin clients and micro PCs that were built to sit quietly on a desk for eight hours a day and are now being cleared out by the pallet. Many are perfectly happy running Proxmox 24/7, and £50 a node is a realistic target if you shop carefully.

The places to look are eBay UK, Gumtree, Facebook Marketplace and local business clearance sellers. Ask the boring questions before you pay: does it include the power supply, is the BIOS locked, has Computrace been disabled, how healthy is the eMMC, and does it actually boot? A listing marked untested can be a bargain, but only if you are comfortable writing off the money.

Picking the tin

You are looking for three things: enough RAM, a storage path that will not die in a month, and a CPU that supports virtualisation without melting. Eight gigabytes is the practical floor for Proxmox plus a couple of containers. Sixteen gigabytes makes the whole thing far less annoying.

Thin clients worth a look

• Dell Wyse 5070: common, quiet and low idle draw. Many come with 4GB and a small eMMC, so check for an M.2 slot and budget for an SSD.
• HP t630 and t640: cheap, fanless in many cases, and fine for lightweight containers. The t640 is quicker, but check the power supply situation.
• Fujitsu Futro S920: older and slower, but often very cheap. Good for a DNS node or a backup target, not for a Windows VM.

Tiny PCs worth the extra

• Lenovo ThinkCentre M700 or M710 Tiny: more upgradable, proper M.2 and SATA options, and easier to find with 8GB or 16GB.
• Dell OptiPlex 3050 or 3060 Micro: plentiful, well documented and usually easy to service.
• HP EliteDesk 800 G3 Mini: a solid little workhorse if you find one at the right price.

A £50 thin client with 4GB and 32GB eMMC will run Proxmox, but it will not run much else comfortably. Add a decent SATA or USB 3 SSD and you have a usable node. Avoid cheap USB flash drives for VM disks; they are not built for constant writes.

The three-node stack that makes sense

A sensible £150 lab looks like this: one node for Pi-hole and Unbound, one for Uptime Kuma, Prometheus and Grafana, and one for test VMs and snapshots. If you buy three nodes, you can form a Proxmox cluster, but do not expect enterprise HA. There is no shared storage, and a single Gigabit NIC per node is normal at this price.

Keep the network simple. A cheap five-port Gigabit switch is fine. If you want separate lab and home networks, use VLANs on a managed switch rather than adding USB Ethernet adapters that may need driver wrangling. Remember that Pi-hole is DNS: if your lab goes down and it is your only resolver, the whole house notices. Run a secondary DNS service on your router or a Raspberry Pi.

Storage is where the compromises bite. eMMC wears out, USB SSDs can disconnect under load, and ZFS will eat RAM you do not have. Use ext4 or LVM-thin on small nodes, keep backups on a separate USB hard drive or NAS, and test a restore before you trust any of it.

Power maths for 2026 tariffs

Assume a unit rate of around 25p per kWh and check your own tariff, because standing charges and regional rates vary. A three-node lab is not a server rack, but it is not free either.

| Setup | Idle draw | Annual kWh | Cost at 25p/kWh | | Three thin clients at 7W plus switch at 5W | 26W | 228 | £57 | | Three at 10W plus switch | 35W | 307 | £77 | | Three mini PCs at 15W plus switch | 50W | 438 | £110 |

Those figures assume 8,760 hours a year. Measure your own idle draw with a smart plug after boot, not during the initial Proxmox install. The difference between a 7W thin client and a 15W mini PC is about £50 a year at these rates, which is worth thinking about before you buy the faster machine.

When a Raspberry Pi is still the smarter buy

If your goal is Pi-hole, a monitoring dashboard and a handful of containers, a single Raspberry Pi 5 with 8GB RAM and an NVMe hat will do it for less money and far less power. It is also quieter and simpler to maintain. Buy the three-node lab only if you need x86 virtual machines, snapshots, clustering practice, Windows testing or isolated networks.

Do not buy three nodes to run one Pi-hole. That is a hobby tax, and you are allowed to admit it. The lab is the cheap part; your time and the electricity are the recurring costs.