My NAS uses a similar amount of power. The drives use most of the power. The PC uses less than 20W on its own. Upgrading to a couple of large helium filled drives will save a good bit of power. SATA drives tend to use a little less power than SAS drives too.
this post was submitted on 06 Jun 2025
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Instructions unclear, now my server is slowly floating into the sky....
Most of the power draw is from the hdds. I have the same issue. If you want less power consumption. Invest in SSD or SSD and HDD hybrid where you store quick access files on SSD and rare access on hdd (then you can spin them down with timeout of , let’s say 30-60 min). This should save some energy
In my experience using a PC as a NAS, the power draw isn't necessarily the drives as they spin down when idle.
I have an old desktop setup as NAS - with 2 drives or eight drives, idle power draw is virtually the same, about 100w, regardless of the OS (Windows, Linux, UnRAID, Proxmox).
I also have an old consumer NAS, with five 4TB drives, and it idles under 20w (I think last I checked it was ~15w... I need to check it again and write that down).
Two very similar systems, one designed to be a NAS, the other a desktop. It really comes down to the motherboard design and capabilities.
I also have a Dell SFF that idles at about 15w, regardless of drive count - one drive or four (and to get four I added a SATA expansion card and rigged some power splitters, really pushing the power supply). That box idling the same, even when pushed well past design, is pretty telling.
And don't think that SSD drives would do better - spinning disk drives generally have far better idle power than SSD does, and usually much better write power consumption.
So it really depends, and mostly on the motherboard itself. Yes, you'll get more power usage with more drives, but that's at write and read time. My SFF idles at 12w, peaks at 80w when converting videos, the read/write power is negligible, same with the NAS (I transfer hundreds of gigs between them every few days).
Good point. I looked mostly at the spec sheet from the manufacturer and for example the Samsung 870 Evo vs Seagate IronWolf NAS Drive. Side note, AFAIK NVME drives have a higher power consumption. Especially PCIe 5.0.
My NAS with 2 HDDs from Seagate has a total powerdraw of around 30-40w. And I don’t spin the drives down.
- Latency of accessing files/loading times
- Lifespan reduction because of spin up / spin down Head moves (the most common for head crash, as I learned from my Teacher)
In my experience using a PC as a NAS, the power draw isn't necessarily the drives as they spin down when idle.
that's not always the default setup, especially with enterprise drives. also if you have some kind of monitoring, that can keep the drives from going down (for that, use linux hd-idle instead of drive internal idle timer), and it can also wake them up (for that, prometheus node exporter's smart collector first checks whether a drive is up, and only then collect stats). Interestingly, checking temps with smartctl always spins up my drives, while linux hwmon can give me live temp stats even while the drives are down
And don't think that SSD drives would do better - spinning disk drives generally have far better idle power than SSD does, and usually much better write power consumption.
I wonder if they can be "spinned down" like hard drives. their startup time would be much faster, so it's shutdown could even be on a tighter schedule. I mean probably they dont have an internal idle timer, but who cares if you can just have something like hd-idle that shuts it down according to a better schedule.
If you can figure out how to get a qnap to spin down its disks, please let me know lol. I've been searching for months and haven't found a reliable solution. I basically only need to access it once a day at MOST, so having the disks spinning away for like 99% of their life sucking down power is something I'd like to avoid. The problem seems to be that even with a perfectly clean slate, no services running, the system set up in their own RAID0 SSD pool, the HDD's, even with 0 bytes of data on them, are being pinged for access at least once a minute. I'm assuming it's some log being written to, but it's not anything visible in the file system, and I haven't been able to find any solution online, lots of people seem to have the same issue.
I'm tempted more and more every day to just grab one of those low-power embedded ITX boards and build up a custom rig. Other than the disk spinning constantly, the TS-462 does everything I need perfectly.
I remember to have it working with default software I got but it was 10 years ago.
Then they added this bloatware like media streaming addon or notification center. I have now entware with minidlna and set minidlna scanning disk once per day because media streaming was scanning all the time.
I haven't figure out how to permanently kill their /usr/local/sbin/ncd, ncdb, qNoticeEngined, qulogdb, NotificationCenter, mariadb processes. If I figure out it it probably start working again.
The problem seems to be that even with a perfectly clean slate, no services running, the system set up in their own RAID0 SSD pool, the HDD's, even with 0 bytes of data on them, are being pinged for access at least once a minute.
if it's for drive health stats, and the device runs linux, hd-idle could help. it only counts actual block device (so, storage) access as activity
They run a custom vendor-locked distro named QTS, so they're not really as easy to modify as a normal system, I don't think you can even install programs like that.
I'll definitely bookmark it though if I ever get around to building my own solution, thanks!
Wow, QNAPS don't spin down disks? Geez, what a crappy design choice. Thanks for that tidbit, I was considering one for my next NAS.
I have no idea if it's a QNAP-wide issue, or just some specific models, I haven't bothered to do that much research. I'm guessing that the discs WOULD spin down if you have that option selected if they weren't constantly being pinged a couple times a minute. That constant pinging is the part I can't seem to track down.
An excerpt from a post I was reading while researching this sums it up prettt well: "700 posts about spindown/sleep/standby not working in the QNAP HDD Spin Down Forum. No one seems to be able to resolve it. Qnap clearly couldn't care less."
The only solution that I've found that seems to work is to install some other operating system on it, which kind of defeats the purpose of buying a turn-key NAS, and is slightly outside my comfort zone right now. I just ordered a kill-a-watt, so I'll see how much power it's taking with/without drives and go from there if it's worth my time to dive into an OS swap, or building a custom rig.
I have an old dell power edge that I got from work that I used as a NAS for a while, it sucked down more juice than the old PC I was using and was stupidly loud all the time. I ended up transferring everything back to my old PC and now that turd just sits there waiting for someone else to be dumb enough to buy it from me. I wouldn't waste the money personally.
The power edge server is going to draw way more power just because it has a "powerful" cpu(s) and other power running components. The Qnap will be much quieter and consume maybe a few watts less power than your existing setup, potentially. I wouldn't use it though because your existing setup is way more flexible on what you can do with it.
"powerful" LOL it's a turd
but yeah my current setup also happens to play games and adding storage is much easier cuz I can just throw whatever in there instead of making sure the drive conforms to some arbitrary crap.
It's "powerful" in the sense that it has 48 PCI lanes and can use almost 800GB of memory (ECC included). This is just way overkill on most homelabs so the extra power draw isn't worth it.
Ah yes, in that context I would agree.
Thank you, this is what I am thinking too. I don't wanna create e-waste, and apart from power consumption, the nas is very handy performance wise and tackles all load.
A big portion of that is caused by the drives, so you'd have to compare the empty QNAP vs your empty machine. Also, depending on which NAS appliance, check that the CPU is actually powerful enough to run all your services.
Drives only consume power on reads and writes, if your NAS spins them down as it should (and apparently QNAP *doesn't, which I didn't know).
As per my other comment - 8 drives or 1 drive, same idle power for desktop hardware. My actual NAS uses about 1/8 the power at idle for 5 drives.
Drives only consume power on reads and writes, if your NAS spins them down as it should (and apparently QNAP *doesn't, which I didn't know).
not really. not all drives spin down by themselves, by default. and even if they do, it'll happen relatively long after reads and writes, a the while it'll consume power.
How do you monitor power consumption? I'm new to self hosting and I want to do that.
I use a KillaWatt device. It is a simple device you plug into the outlet and then plug the device you want to measure into it. I've had mine for a long time so I have no idea what a new one would cost, but I'm guessing sub $30.
I actually have an extension cord with IoT chip. Can measure power consumption via home assistant.
Some local libraries (e.g. in Heidelberg) or ecological initiatives lend devices to measure electricity consumption at the power plug. In particular, this is useful to measure other appliances as well.
Specifically for computers, they probably have some means to tell you their own consumption, but they may not be accurate or complete and will most certainly omit any peripherals, e.g. external hard drives.
Thank you! I will see if I can get my hands on one of those.
"Old PC" meaning what, exactly? Need some specs.
In general, a Qnap or Synology box is going to be much lower wattage than a full PC.
It's 6th gen i5 processor with gigabyte motherboard. And Qnap is ts-531x.
I switched from an I3-530, nominal TDP 73W, to an N-100, nominal TDP 7W, and power from the wall didn't change at all. Even the i3 ran around 0.1 CPU load, except when transcoding, and I'm left with the impression that most of the power goes into HDDs, RAM, maybe fans, and PS losses. My sense is that the best way to decrease homelab power use is to minimize the number of devices. Start with your seyrver at 60W, add a WAP at 10-15W, maybe a switch at 10-15W... Not because of the CPUs, necessarily, but because every CPU every CPU comes with systems to keep the CPU going, keep the power regulated, etc.
Power isn't from drives, if your OS spins them down (as any NAS solution should).
You can only spin drives down if they're idle. If you have a service that touches it - say, homeassistant logging data, tvheadend updating EPG - then they're going to keep spinning.
I would hope one would use an SSD for something like HomeAssistant. HDDs really shine as bulk media storage (music, pictures, video) not as storage for what would be the equivalent of running an OS on it.
Thank you, this is what I needed to know. I thought n100 (similar to what dedicated nas has 6-10w) would bring power down considerably, and thanks to you, I now know it's not the case.
You'll want to look up the QNAP as well. I've seen reports with quite some variety on the power consumption. Depending on the exact model, it could be somewhere in the range from 25W to 55W... So could be less, could be the same. And have a look at the amount of RAM if you want to run services on it.
Ram is definitely abysmal on Qnap, so it's one reason for hesitation. But I wanted to get some idea how much power saving is possible on dedicated NAS. If it's not much, I would rather keep my PC.
Sure, I have an old PC with an energy efficient mainboard and a PicoPSU and I wouldn't want anything else. I believe it does somewhere around 20W-25W though. And I have lots of RAM, a decent (old) CPU and enough SATA ports.... Well, I would go for a newer PC, they get more energy efficient all the time... But it's a lot of effort to pick the components unless some PC magazine writes something or someone has a blog with recommendations.