Running Proxmox VE on a $150 mini PC is fine until you actually want to do something with it — a few VMs, a couple of containers, maybe a Windows box for testing, ZFS with real redundancy. That's when a decommissioned enterprise server starts looking a lot more attractive than another NUC.
Here's how to pick one without ending up with a jet-engine paperweight.
Why an enterprise server instead of consumer hardware
Enterprise rack servers (Dell PowerEdge, HPE ProLiant, Lenovo ThinkSystem) were built for 24/7 operation, have ECC memory as standard, redundant power supplies, and — critically for a Proxmox host — proper IPMI/iDRAC/iLO out-of-band management. You can power-cycle, reinstall, and monitor the box without ever touching a keyboard connected to it.
The tradeoffs: noise, power draw, and rack space. If you're putting this in a bedroom, plan for that upfront (more on cooling below).
What to actually look for
CPU generation. Don't go below a 2nd-gen Xeon Scalable (Cascade Lake, e.g. Xeon Silver 4210) or, for the older PowerEdge 13G line, Broadwell-era E5-2600 v4. Older Haswell/Ivy Bridge (E5-2600 v3 and earlier) parts are cheap but burn far more watts per core than what you'd get today — bad if you're paying residential electricity rates 24/7.
RAM. Buy DDR4 ECC RDIMM, and buy more than you think you need — RAM is the first thing Proxmox exhausts once you start running more than 3-4 VMs plus ZFS ARC. 128GB is a comfortable homelab target and is usually affordable on the used market for these platforms.
Drive bays and controller. Check whether the server ships with a RAID controller (PERC H730/H330 on Dell, Smart Array P440ar on HPE) or a plain HBA. For Proxmox + ZFS, you want an HBA in IT mode, not a hardware RAID controller — if the listing only mentions a PERC/Smart Array, budget for crossflashing it or swapping it for an HBA330/H330 in IT mode.
Network. Onboard 4x1GbE is standard and fine to start. If you plan to do SR-IOV passthrough or fast storage replication between nodes, check whether the server has a free PCIe slot for a 10GbE card later.
iDRAC/iLO license level. Basic remote management is free; virtual media (mounting an ISO remotely to install Proxmox without a USB stick) usually requires the Enterprise/Advanced license. Confirm it's included, since a bare "Basic" license makes the first install noticeably more annoying.
Models that show up often on the used market
- Dell PowerEdge R630 (1U) — dual E5-2600 v3/v4, up to 24 DIMM slots, compact. Good if rack space is tight. Fewer 3.5" bay options.
- Dell PowerEdge R730 / R730xd (2U) — same CPU generation as the R630 but with far more drive bays (up to 16x 2.5" or 12x 3.5" on the xd), making it the better pick if you want a real ZFS pool with several drives.
- HPE ProLiant DL360 Gen9 / Gen10 — similar profile to the R630/R730 line, iLO instead of iDRAC. Gen10 supports Scalable Xeons.
- Lenovo ThinkSystem SR630 — less common used but shows up, similar generation.
For a first Proxmox node, an R730xd with dual Xeon Silver/Gold, 128GB RAM, and an HBA330 in IT mode is a very common and well-documented sweet spot.
Power and noise — the part people underestimate
A 2U dual-CPU server idles significantly higher than a desktop — expect 120-180W at idle depending on drive count and CPU TDP, more under load. That's a real line item if it runs 24/7. Rack fans on 1U chassis in particular are loud at boot and under load; a 2U chassis is noticeably quieter. If it's going in a closet or garage, that's usually fine. If it's next to your desk, budget for either a 2U unit or planning fan curve/BIOS tweaks (which vary a lot by vendor and aren't always accessible without the enterprise license tier).
Proxmox-specific setup notes
- Update the BMC firmware (iDRAC/iLO) and the BIOS/system firmware before installing Proxmox — old firmware is a common source of weird PCIe passthrough and NIC issues.
- Enable IOMMU in BIOS if you want to pass through a GPU or HBA to a VM.
- If you crossflash a PERC to IT mode, do it before installing Proxmox on top of it — reflashing after the pool is created will make ZFS see a different controller and can complicate imports.
- Set up email or Discord/webhook alerts in Proxmox for drive and node health early. Used drives are used drives.
Buying tips
Sellers will usually list CPU model, RAM amount, and drive bay count, but often skip whether it includes rail kits, the RAID controller model, or the iDRAC/iLO license tier — ask before buying if it's not in the listing, since those three things are exactly what determine whether the box is ready to rack-and-go or needs extra parts. Tested/burned-in units cost a bit more than pure auction pulls but save you the risk of a DOA PSU or a server that throws memory errors the first week — for something running unattended, that premium is usually worth it. If you'd rather skip auction-sourced gear entirely and buy something already tested and reset, resellers like IT and Office list refurbished rack servers with the specs already listed per unit.
What's everyone else running as their main Proxmox node — still on Broadwell/v4 Xeons, or have you moved to Scalable/Epyc used gear yet?
