If you own a NAS, you’ve probably noticed just how noisy those spinning platters in hard drives can be. Common online advice often suggests spinning them down when they’re not in use to eliminate the noise and save power. On paper, it makes a lot of sense, but real-world use tells a different story—for many people, keeping them spinning actually makes more sense.

Constant spin cycles cause wear and can lead to premature hard drive failure

Repeated spin-ups aren’t as harmless as they seem

Mechanical hard drives are one of the few computer parts with moving parts, and like any moving part, this makes them more prone to failure. It stands to reason that a hard drive that’s always spinning might experience more wear and potentially lead to premature failure.

However, the spin-up cycle is one of the most mechanically stressful events a hard drive goes through. The internal motor has to overcome inertia to bring the platters up to several thousand RPM, and the heads load and lift off the disk.

This is reflected in the brief power surge, during which a hard drive can draw around 10–15W (sometimes slightly higher on larger drives) for a few seconds while it spins up. When the drive spins down, the heads park on a ramp system, and while modern drives are designed to avoid platter contact, improper parking or rare mechanical issues can still increase risk over time.

General-purpose hard drives are designed to handle these spin-down and spin-up cycles, but it doesn’t change the fact that the moving parts of the drive experience additional mechanical stress during each cycle.

Now compare that to a drive that’s always spinning. The platters avoid repeated start-up shock, the bearings operate at a steady speed, and the motor runs under stable conditions rather than repeated acceleration and deceleration. This still causes mechanical wear, but it is slow and continuous rather than cyclical.

As a side note, NAS-specific hard drives are designed for this kind of 24/7 operation and are rated to run continuously for many years.

Storage Capacity

8TB

Compatible Devices

SATA

The WD Red Plus hard drive line is designed specifically for NAS usage. This means the drive is build to withstand 24/7/365 usage, with up to a 180 TB per year workload rate. You’ll also get a 3-year warranty with the purchase of WD’s Red Plus drive lineup.

Another factor is thermal expansion and cooling cycles. A drive that’s always spinning operates at a relatively stable temperature, whereas one that frequently spins up and down repeatedly heats and cools. This can introduce minor, microscopic stress on components like solder joints, bearings, and other internal materials over time.

All of this means that aggressive spin-down behavior can, in some scenarios, contribute to additional wear compared to continuous operation. Don’t take my word for it—QNAP, a major NAS device manufacturer, also recommends avoiding frequent spin-ups and spin-downs due to the additional wear.

The actual power savings are smaller than most people think

You hardly save anything by spinning drives down

Credit: Jordan Gloor / How-To Geek

 

Let’s be honest: the main reason most people allow their NAS drives to spin down isn’t wear (though it absolutely should be), it’s noise and power draw. A hard drive that’s in standby mode typically draws a fraction of a watt. In contrast, a drive spinning idle without active reads and writes can draw around 5–10W depending on the model. 2.5-inch hard drives use a fraction of this, though you probably shouldn’t use one of those in a NAS for other reasons.

In the context of a typical household, this is still very little—roughly comparable to a single LED light bulb. Even if a drive runs 24/7/365 at around 8W, that’s about 70kWh per year. At around $0.16 per kWh, that works out to roughly $11.20 per year. Granted, that isn’t nothing, but the hard drive will also draw more power during actual read/write activity, so the real-world difference is even smaller.

If you have a dozen hard drives spread across multiple NAS enclosures, the combined cost of keeping everything spinning might start to add up to something more noticeable. But that’s an edge case. Most people only have a few drives, meaning the total power draw rarely becomes a meaningful cost in practice.

My NAS is in constant use, and I only have one hard drive

Real-world usage is the most important factor

Credit: Ismar Hrnjicevic / How-To Geek

I use a laptop with an external hard drive connected as a NAS media server, and it’s set up to run 24/7. In the context of today’s topic, this means two things: first, I don’t really have to worry about power consumption because I’m only keeping a single hard drive spinning, and second, I really, really don’t want that drive to fail.

I keep multiple copies of my important work files and photos, but the vast majority of my media only exists on this one drive. Losing it wouldn’t be the end of the world, but it definitely wouldn’t be a pleasant experience either.

Since I prioritize minimizing the risk of hardware failure, it makes more sense to spend a few extra dollars per year keeping the drive spinning than constantly letting it enter standby mode.

My wife and I are constantly accessing the NAS to stream media, access and back up work files, and automatically sync photos through Immich. In practice, that means the drive would likely spin up and down dozens of times a day, which defeats the point of aggressive spin-down settings in the first place.

Besides, if the drive does fail, replacing it isn’t exactly cheap given current storage prices.

Aside from longevity, another major benefit of keeping the drive spinning is instant access. Instead of waiting 5–10 seconds for the drive to spin up before files start loading, all my media and work files remain immediately accessible.

If you want to let your hard drives sleep, you should pair them with an SSD

SSDs make spin-down setups viable

If you have several hard drives in your NAS and care more about reducing power draw than minimizing mechanical wear, or if you simply don’t access your files that often, letting the drives spin down can still make sense. But for active home servers that are in constant use, aggressive spin-down settings create more problems than they solve.

If you want the best of both worlds, you can pair the hard drives with an SSD, which you can then use for frequently accessed files and apps. Just don’t go overboard.