The first question anyone asks before building a home server is whether the machine they already own will run it. The makers publish answers, but they publish different amounts of detail, and all of them publish a number that is lower than what you should actually plan for.

What each maker states

Proxmox VE gives a minimum of 1 GB of memory, plus whatever the virtual machines themselves need, on its system requirements page. It also publishes a separate recommended figure, which is considerably higher, and adds roughly a gigabyte per terabyte of storage if you use ZFS. It does not state a minimum disk size at all, only that you need a hard drive.

TrueNAS is the most specific of the three. Its hardware guide gives 8 GB of memory and 20 GB of boot storage. That is a much higher floor than Proxmox’s, and it reflects that ZFS is not optional here: it is the whole point of the product.

OpenMediaVault is the most honest of the three about the gap between booting and running well. Its prerequisites page gives three tiers rather than one number: 1 GiB as the minimum, 4 GiB as the better figure, and 8 GiB or more, ideally in two matched modules, as its actual recommendation. Like Proxmox, it gives guidance on drive types rather than a minimum capacity in gigabytes.

Unraid publishes neither a memory minimum nor a disk minimum that we could find. We have left both blank rather than repeating a figure from a forum post, because a number with nobody’s name on it is worse than an admitted gap.

Why the stated minimum is the wrong number to plan with

A published minimum answers one question: will this boot. It does not answer the question you are actually asking, which is whether the machine will do the job without irritating you.

Proxmox’s 1 GB is the clearest example. It is true, and it is useless on its own, because Proxmox exists to run other machines inside itself and each of those needs its own memory on top. A host that boots in 1 GB and has nothing left to give its guests has not achieved anything.

TrueNAS’s 8 GB looks stricter but is doing the same thing. ZFS uses spare memory as a read cache, and gets meaningfully faster with more of it. Eight gigabytes gets you a working system. It does not get you a fast one.

The useful way to read these numbers is as a floor to stay above, not a target to hit.

The one that catches people out

Memory is the component people underspend on, because the minimums make it look unimportant, and it is also the one that is hardest to change later on the small machines this hobby runs on.

Many mini PCs take two memory modules and a great many laptops-turned-servers take one. Working out what the machine tops out at is worth doing before you buy, not after you have outgrown it.

Storage is the opposite: easy to add later, and the thing you will genuinely need more of. Plan for the disks to grow.

What none of them tell you

None of these pages mentions the two things that actually decide whether a home server is pleasant to live with.

Noise. The machine is in your home. Enterprise hardware bought cheaply second hand is superb value and sounds like a hairdryer. This is the single most common regret in the hobby, and no specification page will warn you.

Power. A server running every hour of the year is a standing cost. The difference between an efficient mini PC and an old desktop repurposed as a server is easily a few hundred kilowatt hours a year, which at UK prices is a real number rather than a rounding error.

Neither appears in any requirements document, because neither is a requirement. They are just the two things you will care most about six months in.

The honest summary

If you are shopping, aim for 16 GB of memory and stop worrying about the published minimums. That comfortably clears every floor on this page, leaves room for the virtual machines or apps you will inevitably add, and costs little enough on current hardware that the saving from going lower is not worth the ceiling you buy into.

If you are checking whether a machine you already own will do, the answer is almost certainly yes for a storage-focused system, and depends on the memory for a virtualisation one. The figures above are the test. Just remember which release they were checked against, because they do move: the Proxmox release notes are where changes to its requirements are announced.