Most NAS drives will accept SSDs as well as mechanical hard drives - but is it a good idea?
Most NAS drives will accept 2.5in drives, opening up the intriguing option of populating them with SSDs. But is it a good idea? The main attraction of solid-state storage is its exceptional performance - but in this context that's largely moot. A gigabit Ethernet connection can only handle transfer speeds up to around 110MB/sec, so unless you're willing to spend serious cash on 10GbE hardware, you'll see no benefit from faster drives.
That's not to say the SSD route is completely without merit. We tested the Qnap TS-453B using four 2.5in SATA SSDs, and saw a slight improvement in 4K read speeds - up from 10.4MB/sec to 11.4MB/sec.
And if you've ever sat next to a four-bay NAS appliance, you'll know that the combined noise of four mechanical hard disks all grinding away can be quite distracting. Since SSDs have no moving parts, they run silent, so the only sound from your NAS will be the internal fan.
SSDs also use less power than mechanical disks. Our four-bay Qnap TS-453B, populated with four 1TB Seagate Barracuda 3.5in hard disks, drew 32W from the mains while sitting idle, and 38W while streaming video; switching to four SSDs saw this plummet to 14W idle and 16W while streaming. You'll see a similar drop regardless of which NAS enclosure you choose.
The catch is the cost. A 1TB mechanical disk can be had for $60 or, so you can set up a 3TB RAID 5 array for not much at all. The very cheapest 1TB SSD, will set you back around $350 - so you're looking at a cool grand for the same amount of storage. Even for a quieter, more energy-efficient NAS appliance, it's hard to justify such a huge price differential, especially when you remember that performance will be basically identical.