OWC ThunderBay 8

OWC ThunderBay 8 review: loads of space, room for improvement

Upgrading from a 5-bay Drobo 5D to a new OWC ThunderBay 8 to store and protect my photos and videos. Here's what's good and not-so-good about this direct attached storage device.

For years I've stored photos and videos using a Drobo 5DT. The device has worked well (three hard drive failures with no data loss), but I recently ran out of space, and with the company going bankrupt it seemed like a good time to migrate to a newer, faster storage device. After doing considerable research, I landed on the OWC ThunderBay 8.

  • Loads of storage (128TB max)
  • Fast enough for editing 4K video directly from drives
  • Multiple RAID volume options
  • Easy setup and configuration, connects directly to Mac or PC
  • Mounts on desktop as a normal, external drive
  • Noisy internal fan
  • Provided USB-C cable is far too short
  • Weird front latch and key lock design
Check current price: OWC ThunderBay 8

OWC ThunderBay 8 overview

The OWC ThunderBay 8 is basically a big box of hard drives. Drives may be mounted and used individually, or joined together to form single RAID volumes. The latter appears as one giant drive that looks and feels like a normal, external hard drive (but with loads of space), and provides protection should a hard drive fail (if configured as RAID 5 — more on that in a minute).

This type of hardware is known as a "DAS" — a Direct Attached Storage device. It provides similar functionality to a "NAS" (Network Attached Storage device), but connects directly to a Mac or PC instead of being accessed like a server over a local network.

Adding drives

There are eight slots for standard 3.5" SATA hard drives and/or 2.5" SSD drives in the ThunderBay 8. Any size or brand of drive may be used. You may also mix SATA and SSD drives, use a subset of drives as a single RAID volume, and mount individual drives as well. This means some drives could be merged to create a RAID protected volume, and other drives (like an SSD) could be used as standalone cache or proxy disks for video.

Whatever type of drives you choose, the maximum storage capacity of the ThunderBay 8 is 128 TB, which is equal to eight 16 TB drives.

For my ThunderBay, I installed four WD 14TB Red Plus 3.5" NAS drives. These are 7200rpm drives designed for the rigors of DAS and NAS hardware. I was tempted to buy faster, more modern SSDs, but their cost would have been prohibitively expensive for my data storage needs.

Western Digital 14TB WD Red Plus NAS drive

Connecting the ThunderBay 8

The back of the ThunderBay 8 has a security lock, display port and two Thunderbolt 3 / USB-C ports. One USB port is for connecting the ThunderBay to a single Mac or PC (cable included), while the other may be used to daisy-chain another ThunderBay for more storage, connecting an external drive, peripherals, or a monitor. You may also connect a second monitor to the display port.

Two Thunderbolt 3 / USB-C ports and one display port

With the display port and second USB-C / Thunderbolt 3 port, the ThunderBay 8 can power two 4K monitors. This is great for dual monitor setups, for then a single cable is all that's needed to connect a Mac or PC to the ThunderBay.

Creating a RAID volume

Drive initialization and formatting is handled through SoftRAID XT. This is third party macOS and Windows software developed in partnership with OWC.

SoftRAID XT supports volumes using RAID 0, 1, 0+1, 4, 5 or JBOD. If you don't know what that means, these are levels of protection that control how data is split up and written across the drives. SoftRAID XT provides information to help you decide, but for average users, RAID 5 is typically the best compromise of speed and security.

After creating a RAID 5 volume with four WD drives, my total disk capacity dropped from 56 TB (14 TB x 4) to 42 TB. This is part of the reason why it's important when building a DAS or NAS system to buy more drive space than you need to account for RAID mirroring. (Here's a helpful calculator).

42TB RAID 5 volume comprised of four 14TB drives

I had no trouble installing drives, initializing the SoftRAID software, and formatting a single RAID 5 volume. There is a little bit of weirdness on macOS where drive security settings must be changed to allow third party software apps like SoftRAID to function, but it's easy to do.

All told, I had my ThunderBay 8 set up, mounted, and ready to go in less than 30 minutes.

Speed test

After successfully building and mounting the ThunderBay, I used Blackmagic Speed Test to see how fast I could push and pull data from the RAID 5 volume. On average, I got ~550 MB/s write and ~700 MB/s read. For me, this is plenty fast for editing raw photos in Lightroom, PSDs in Photoshop, and editing 4K video in Premiere and DaVinci Resolve.

ThunderBay 8 Read/Write Speeds w/ four 14TB WD 7200rpm NAS drives 

Things I don't like about the ThunderBay 8

Overall, the ThunderBay 8 is working well for my photo and video storage needs. The Thunderbolt 3 speeds are fantastic, and I have plenty of room to grow in the future. There are, however, some things that could be improved.

I really don't like the latched gate on the front. It's surprisingly difficult to remove and lock back into place. The sides must be lined-up just so to sit flush. Otherwise the plate can get stuck at awkward angles. There's also a key lock for added security, which I guess is a good idea for workspaces with other people around, but the mechanism feels flimsy, and I worry about losing the keys. The keys can also vibrate and make noise when the ThunderBay is running, which brings me to my next point.

It's twice as loud as my Drobo. The fan is very noticeable in a quiet workspace. Obviously something is needed to keep the enclosure and internal drives from overheating, but I was hoping for quieter hardware this go around, not louder. The fan turns on when a USB-C cable is connected and runs continuously at a fixed speed when a PC/Mac is awake. There also doesn't appear to be any sound dampening inside, so it's easy to hear the hard drives crunching and rattling around. The noise is better when moving the ThunderBay further away, but that brings me to my next point...

Big fan on the back that runs constantly

The Thunderbolt 3 / USB-C cable is only 2.5' long. This is long enough when the ThunderBay is sitting next to a PC or Mac, but otherwise is too short. To get my ThunderBay 8 on the floor, behind my desk, away from my desktop Mac Studio, I purchased a longer OWC Thunderbolt 4 / USB-C cable (which is backwards compatible with Thunderbolt 3). A longer cable in the box would be much better.

RAID volumes cannot be expanded. This may be more of a SoftRAID thing than a ThunderBay thing, but at the time of this review, new drives cannot be added to an existing RAID volume. The only way to expand a volume is to backup the ThunderBay's data elsewhere, format a new (larger) RAID volume, then move the data back. This was one of the Drobo features I especially liked, for I could add or replace drives anytime to increase storage capacity. SoftRAID can't do that, so it's better to buy more storage and build larger RAID volumes at the get-go.

Too big, too expensive?

With a maximum capacity of 128TB (112TB as a RAID 5 volume), the ThunderBay 8 may be overkill for photographers who only need to store raw photos and PSDs. For those users, OWC also sells the smaller, less expensive ThunderBay 4 with four slots (max capacity 72TB) instead of eight. Identical setup and functionality to the ThunderBay 8, but half the size and capacity.

The importance of cloud backup

Last but certainly not least, it's important to point out that neither the ThunderBay 8, nor any other external DAS or NAS, is a one-shot solution for data backup. Data can and will be lost if a ThunderBay is stolen, damaged, or suffers a complete meltdown.

Therefore, it's important to backup the ThunderBay's data someplace else—preferably in the cloud. For the latter I use Backblaze. It's simple, easy to setup on macOS and Windows, runs invisibly in the background, and uploads files continuously (or on a schedule) with no limits on storage. You can upload as much or as little data as you want for one monthly fee.

Backblaze was part of the reason I bought another DAS (like the Drobo) instead of a NAS system from Synology, Qnap or others. NAS enclosures are networked drives, which means they fall under a different, more expensive category of cloud backup service. But because DAS systems (like the ThunderBay 8) connect directly and mount as local drives, they are compatible with Backblaze's more affordable personal backup plan.

Additionally, if I need to, I can download files from Backblaze when not at home. For example, if I forget an important file on the ThunderBay 8 while traveling, I can get the latest backup of that file (or files) from Backblaze using my web browser. For me this removes any need for a NAS system, for with Backblaze I can still (in a roundabout way) access my ThunderBay 8 data from anywhere.


Overall, the ThunderBay 8 is a good upgrade from the Drobo 5D with increased storage capacity, 2.5" SSD drive support, faster read/write speeds, Thunderbolt 3 power and expandability, plus additional ports for adding peripherals. I won't truly know how well the ThunderBay and SoftRAID XT software works until encountering my first drive failure (knock on wood), but will update this post when and if that happens.

For photographers and/or videographers who want immediate access to large amounts of data, with protection against single hard drive failure, the ThunderBay 8 does do the job. I wish the enclosure had better sound dampening, a quieter fan, and a better gate design, but the read/write speeds are way faster than my Drobo, and I very much enjoy the convenience of accessing all my data and editing video directly off the ThunderBay.


OWC ThunderBay 8 Review