Can one person who knows something about media servers / NAS make me a PC config ? Just to evaluate the budget.
Seeing that 4-bays NAS are super pricey I thought it wouldn't hurt to see what it would cost with a small PC.
I suppose you don't need a monster for that.
This is as close to my config as I can get:
https://uk.pcpartpicker.com/list/fytzmr
My build is completely overkill, though. So don't get sticker shock at £1200. I built it out of parts I was using for other things, and you can build an excellent NAS for a fraction of this cost, especially if you already have the HDDs.
In fact, if you are on a tight budget, maybe consider buying a second-hand server or Mini ITX PC from eBay and moving the whole thing into a better case. For £400 I saw a 10 core XEON with Nvidia M2000 GPU, 64GB RAM and 256gb NVMe. Pop that into a case with good airflow and space for a bunch of HDDs (see below) and you'd have an all-singing, all-dancing home media server. And even that might be overkill depending on what you plan to do with it. I've seen some people use a 10th gen Core i3 with a NAS on a super tight budget (about £300-£350 not including HDDs), but their Plex server only does 1080p transcodes to one device at a time.
I'll give you my rationale for all the parts:
Intel Core i5-11400 + Motherboard + Cooler
This is actually a spare CPU from an old mini-PC I built that I no longer used. Before this I was using an i7-6700K and having literally no issues, so an 11th Gen Intel i5 is probably overkill by quite a bit. Motherboard is Mini-ITX, which is required for the case. The cooler was part of the old build that was tight on space, but you probably have scope to use a bigger cooler in the Node 304. That said, at 65w doing NAS tasks I've had no issues in the Node 304, which provides a lot of airflow to the components. What I'll say is with that CPU, I have never had an issue transcoding any video file.
Corsair Vengeance LPX 32gb
You can probably get away with 2x4gb or 2x8gb on a pure NAS server. The reason I've chosen 2x16gb is because I use my RAM as a transcoding drive for Plex and the 8gb I originally built it with was not up to the task. If you're not likely to do any transcoding, you won't have such heavy RAM requirements.
500gb NVMe SSD
Cache drive. So when I write to the NAS, it writes files to the cache drive first before they propagate to the array of HDDs. This means I can use most (if not all) of my 2.5gigabit network speeds when writing to the array. If you don't have a cache drive, you'll be hamstrung by the write speed of the array. Using a SATA SSD is fine for cache too, but you lose one of your SATA ports by doing this and while the SATA SSD may be cheaper up front, it means you only get 3x HDDs, which means you'll be hitting your capacity sooner and buying a SAS card to expand your storage. It's cheaper in the mid-to-long term to use an NVMe SSD as your cache, the bigger the better.
HDDs
Use whatever you want. One thing I'd recommend if you're using Unraid is to set a drive the same size as your largest storage HDD aside for parity. Parity lets you swap out any drive for one up to and including the same size as the parity drive at any time without losing data.
So if you look at my config, I've got 1x16tb as parity, and 1x16tb + 1x8tb + 1x4tb as storage. This gives me 28tb (16+8+4) total storage on the array, and I also get parity. So because I have parity, if any of my three storage devices breaks, I can replace them with a drive of equal or greater size (up to the size of parity, which is 16tb) and I won't lose any data. I just switch the drive out, tell Unraid to restore parity and wait 24 hours and my NAS is operational with all my data intact.
This also means I can switch either the 8tb and 4tb drives each with a HDD up to 16tb in size and Unraid will restore parity. Once parity is restored, I can then replace the other drive for a total of 3x16tb storage and 1x16tb parity.
Fractal Design Node 304 Mini ITX + 400W PSU
This case has great airflow. It can fit 6 HDDs in the front, and the front-mounted fans blow cool air across those 6 HDDs, then across the CPU, and then it gets expelled out the back. And if you're prepared to sacrifice 2 HDD slots (meaning you can still fit 4 in this case) you can fit a GPU in this case.
The PSU is basically the cheapest Gold rated PSU I could find on PCPartPicker. I have a 500W Bronze in mine but I'm gonna swap it out when I've got a bit of money.
This list doesn't include a 32gb USB stick needed for your Unraid installation (it installs to a USB stick, not an internal drive), and the Unraid license.
If you want help using Unraid and what software is good, the
SpaceInvaderOne YouTube channel is an incredibly valuable resource. He shows you how to do all the cool shit with Unraid and nearly everything I do on my server comes from his channel.
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As a follow up,
Li Kao - if I were building an absolute barebones NAS, here's the config I'd use:
https://uk.pcpartpicker.com/list/Lrnxhk
For this one, I've gone with an i3-12100, a bigger fan (it's basically the cheapest), a cheap-ass motherboard, and only 8gb RAM in dual channel.
But a build like this comes with compromises.
The CPU is fine, and as a bare minimum it comes with onboard graphics so you can get into the bios and such without plugging a GPU in.
Your RAM is slower, which probably won't matter for storage, but there may be things you want to do on your server in the future that can benefit from faster (and more) RAM.
No SSD (but there's an NVMe slot for a future upgrade) so out of the gate you don't get any cache, so writing to the drive is gonna be slooooooow.
The case is the same as the one I have. I just frickin' love this case.
This comes in at £415. But if you shop around for a Mini-ITX PC on eBay you can get a much better second hand PC for the same price. The parts may be a little older, but for NAS purposes they do an absolutely fine job.