Stop Paying High for NAS: A Used PC Offers More Value

Understanding the Basics of a Used PC for NAS

Buying a used PC or repurposing your old computer is one of the most inexpensive ways to get a network-attached storage device (NAS). While specialized NAS units exist, they will cost you hundreds of dollars more than just picking up a cheap PC or using one you already own. NAS PCs aren't exactly demanding in terms of hardware, but you still need them to tick certain boxes to make sure you're not wasting your money.

What Makes a Used PC Good for NAS Duty

Most PCs can be turned into a NAS, but there are some key things to consider. Before getting into the nitty-gritty of what kind of hardware your NAS needs, think about the kind of workloads you're planning to use it for. Is it pure file backup, or maybe Plex/media streaming? Docker/VMs? Time Machine backups? There's a lot of overlap in terms of specs here, but certain workloads call for specific hardware. Straight-up storage is the easiest and least demanding to build around.

If you're planning to stream video, try to find a PC with an Intel processor from the last decade or so, as those come with Quick Sync, a dedicated video encoding and decoding hardware core. You can still turn an AMD PC into a NAS, but if your main goal is streaming, consider adding an inexpensive GPU to handle those video-related workloads.

There's no need to buy the latest hardware. Older, reliable PCs make the perfect base for a NAS. You want something sturdy that's not going to set itself on fire from running 24/7 and potentially handling lots of read/write operations on any given day.

You can run a regular Linux distro or even Windows on your NAS, but for most people, the easiest option is to run a NAS-focused operating system like TrueNAS (free) or try out Unraid (paid).

Other than your choice of CPU, make sure the PC you're buying has enough RAM. We're in the midst of the RAM-pocalypse, making memory super pricey, so you're better off buying something that already has at least 8GB as a baseline, or 16GB if you want some headroom for things like apps, Plex, or VMs.

There's also the question of using ECC (error-correcting) memory for better data integrity and stability. Not all CPUs and motherboards support ECC, and you're unlikely to find this in any old used prebuilt off of Facebook Marketplace, though.

If you're looking to buy a used prebuilt, the Dell Optiplex is a popular choice for first-time NAS users. Those PCs were built for work environments where they're hardly ever turned off, so that's a good starting point.

Storage Bays and Expansion Slots Matter Most

Your NAS needs to be big enough to match your needs. Most standard SATA HDDs will work in your NAS, but you need enough drive bays and SATA ports to support them.

There's some argument to be made for buying specialized HDDs to use in a NAS, though. Technically, any 3.5-inch SATA drive will fit, but CMR drives are generally a safer, better option for NAS than SMR. Still, if you're trying to save money, you can absolutely mix in regular desktop drives as long as they're healthy and not ancient. HDDs are still the go-to for bulk storage.

The ideal PC for a NAS will have enough room to hold all the 3.5-inch HDDs you're planning on having, but also a couple of slots for SSDs.

In an ideal world, you'll use the motherboard's M.2 slot for an NVMe SSD that'll work as your boot drive. Consider also picking up an SSD to use as a cache in your NAS. Keep in mind that the motherboard's M.2 slot may share bandwidth with a SATA port, which means that if you use the M.2 slot, you'll have fewer functioning SATA ports.

If the PC doesn't have any support for NVMe SSDs, just go for a 2.5-inch SATA SSD, as that'll still be a massive improvement over an HDD.

Finding a PC with a case that has enough room for all your storage needs can be the biggest challenge. Small form factor desktops often don't have enough storage bays, and the same can be said about cheap OEM desktops, but also high-end cases made for new PCs. Consider how much you want to spend. You can always swap to a different case if you find a PC that ticks all the boxes, but doesn't come with enough storage bays.

Watch Out for Power Efficiency and Cooling

You don't need a beastly cooling solution—it's all about stability. As mentioned, whether you're repurposing your old PC or buying a used PC from someone else, you don't need a monster PC. In fact, it's much better if you don't use one of those for turning it into a NAS.

If you can choose, aim for a system with a lower-TDP CPU, as that accounts for a lot of power consumption and heat. You won't have much of a say in your choice of power supply when buying a used PC, but if you can pick, aim for an 80 Plus Gold or better PSU to improve that efficiency factor.

Proper airflow can give some extra life to your HDDs, but again, this is not something you'll have a lot of say in when buying a random prebuilt. Small OEM cases might have adequate cooling to meet the thermal needs of your NAS, but they can end up being loud.

Don’t Forget Networking Features

Your NAS needs to be able to keep up. You're most likely fine on the networking front, but you should still always check. Older motherboards come with 1Gb Ethernet as a standard, but many newer boards feature 2.5Gb. As 2.5Gb happens to be the sweet spot for home networking, if you can find a PC that has one, you're in luck.

If the motherboard doesn't support 2.5GbE, check that it'll have a free PCIe slot. You can always add a multi-gig network interface card (NIC) to boost the speed yourself.

You can get away with 1Gb Ethernet in your NAS PC, of course. But it's good to think of the future, and being able to slot in an extra NIC can help massively down the line.

Tips to Make Sure You Buy the Right PC

Always be cautious when buying a used PC. If you're using a PC you already own, you know the full state of it. Buying a used computer from someone else can be a bit of a risk, though.

Here are some things to keep in mind when choosing a used PC as a NAS:

• Ultra-cheap small form factor business desktops often won't have a lot of 3.5-inch drive slots
• Old gaming PCs may come with components that are far from power-efficient
• PCs with discrete GPUs may benefit from undervolting later
• Buying anything from people you don't know is always risky, so shop on trustworthy platforms
• Facebook Marketplace can be a good source of old, used PCs, but only if you're careful

A used PC can make a great base for a NAS. In fact, this is one of the best ways to repurpose an old computer. You may not get the best power efficiency or the greatest storage capacity, but you'll still build a home server at a much lower cost.