Per conventional wisdom of portable storage: If you get a Thunderbolt 3 (or 4) drive, it won’t work with USB despite fitting perfectly into a USB-C port.
That changed on October 5, 2022, when the SanDisk Professional PRO-G40 SSD, the latest in Western Digital’s PRO storage lineup, arrived. And the new external storage device proved to be WD’s best portable SSD to date in my testing. It has (almost) everything you’d wanted.
In fact, the PRO-G40 SSD is the answer I’ve been looking for since the Samsung X5 I tested some four years ago.
Here’s the bottom line: If you’re looking for a super-fast portable SSD that can do it all at the current hefty street price of $499.99 for 2TB and $299.99 for 1TB, the new PRO-G40 SSD is still an excellent buy. Get one today!
Dong’s note: I first published this on October 5, 2022, as a news piece and updated it to an in-depth review on December 12 after hands-on performance testing.
Table of Contents
SanDisk Professional PRO-G40 SSD: A rugged portable drive that works everywhere
The new PRO-G40 SSD is the latest in Wester Digital’s portable PRO storage for the processional under the SanDisk Professional brand.
As such, the new drive’s design reminds me of the PRO-BLADE Transport. The main difference is that the G40 is a complete portable SSD with faster speeds and versatility.
It’s also compact enough to fit into one’s palm and weighs just a quarter of a pound (120 grams).
The new portable PRO-G40 SSD is rugged and can take some beating. WD says it features IP68 dust/water resistance, up to 4000-pound crush resistance up to 3-meter drop resistance. Consequently can withstand the elements of any working environment.
In my trial, I tossed it a round a few times and left it outside on the lawn under heavy rain overnight, and the drive survived intact.
Rugged design, super-fast speed
On the inside, the new PRO-G40 SSD checks all the boxes for a dream portable drive. Almost.
First, it’s a Thunderbolt 3 drive that can deliver up to 2700MB/s of copy speed. If you have a USB-C port, it also supports USB 3.2 Gen 2 (10Gbps) with up to 1000MB/s performance.
And you can move from one standard to another seamlessly. The only difference is that it performs faster with Thunderbolt 3.
The drive uses a WD_BLACK, a variant of the SN750, as its storage.
WD PRO-G40 SSD: Hardware specifications
|SanDisk Professional PRO-G40 SSD|
|Standard||Thunderbolt 3 (40Gbps)|
USB 3.2 Gen 2 (10Gbps)
(Will not work with USB-A)
|Internal Storage||NVMe SSD|
|Compatibility||macOS 10.13 and later, |
Windows 10 and later
|Default File System||APFS (Mac)|
|Dimensions||4.36 x 2.28 x 0.47 in |
(111 x 58 x 12 mm)
|Weight||1TB: 0.27 lbs (121.2 g)|
2TB: 0.27 lbs (122.3 g)
|Data Transfer Rate|
(via Thunderbolt 3)
|Thunderbolt 3: Up to 2700MB/s read and 1900MB/s write|
USB-C: Up to 1050MB/s read and 1000MB/s write
|Operating Temperature||41o-95oF | 5o-35oC|
|Ruggedness||IP68 dust- and water-resistant|
4000 lbs crush resistance
3-m drop resistance
A frill-free plug-and-play portable drive (for Mac users)
As you might have noted from the table above, the PRO-G40 SSD doesn’t have everything one might want from a portable drive.
For example, it doesn’t support hardware encryption or any built-in protection feature — you’ll need third-party software if you want to keep your data safe against prying eyes.
On top of that, its rated performance with USB could be better — it doesn’t support USB 3.2 Gen 2×2 (20Gbps).
Out of the box, the PRO-G40 is formatted with the APFS file system to work with a Mac immediately. Windows users can reformat it into NTFS or the exFAT system if they want to interchangeably use the drive with the two platforms.
While the drives work with any host with a USB-C port, it performs best when used with Thunderbolt 3, which is supported in all new Macs.
And by the way, in my experience, the drive will not work with USB 2.0 or any USB-A port. You must use it with a USB-C (or Thunderbolt) port. That’s not a huge deal unless you want to use it with older computers.
SanDisk Professional PRO-G40 SSD: Detail photos
SanDisk Professional PRO-G40 SSD: Excellent performance
For this review, I used the new SanDisk Professional PRO-G40 SSD for an extended amount of time and found it quite satisfying. The super-fast speed aside, the fact that I could use it with any USB-C port has made life much easier.
I tested the drive via Thunderbolt 3 and USB 3.2 Gen 2 (10Gbps) ports, and it worked without any issues.
Since most slower USB standards — USB 3.2 Gen 1 (5Gbps) and below — use the USB-A port type, I couldn’t test the PRO-G40 at any lower USB grades.
It’s worth noting that the drive can get a bit warm, but it never became hot enough to cause concern. Overall, it proved to be a solid little portable SSD that could.
SanDisk Professional PRO-G40 SSD's Rating
Thunderbolt 3 and USB 3.2 Gen 2 support; fast NVMe-based performance
Rugged, water-resistant, compact design
Thunderbolt 3 cables included
Expensive; no USB 3.2 Gen 2×2; only works with USB-C ports
A bit pricey
Reformat required for Windows
Runs a bit warm
The SanDisk Professional PRO-G40 SSD is excellent for anyone who needs a portable SSD that’s rugged, fast, and works across platform and connection standards. Currently, it’s one of a few that can handle both Thunderbolt 3 and USB interchangeably.
In a way, it’s a storage device that helps blur the line between these two connection standards that share the same USB-C port type. And that’s a good thing. The fact it’s also super-fast and rugged doesn’t hurt. Get one today!