The SanDisk Professional Pro-G40 SSD is a versatile portable storage solution for digital files. It comes in three capacities – 1TB, 2TB, and 4TB, and is compatibility with both Thunderbolt 3 (40Gbps) and USB 3.2 Gen 2 (10Gbps) connections. When used with the supplied USB-C style (Thunderbolt 3) cable its NVMe technology is claimed to deliver data transfer read speeds of up to 3000MB/s and write speeds of up to 2500MB/s.
While the Pro-G40 SSD is supplied formatted for use with Apple Mac computers, it can be reformatted to work with Windows machines.
SanDisk Pro-G40: Specifications
Max read speed: 3000MB/s
Max write speed: 2500MB/s
Available capacities: 1TB, 2TB, 4TB
SanDisk Pro-G40: Key Features
On Western Digital's website, the SanDisk Professional Pro-G40 SSD is listed as having read speeds of up to 3000MB/s and write speeds of up to 2500MB/s via a Thunderbolt 3 connection. This performance diminishes to a maximum of 1050MB/s (read) and 1000MB/s (write) when a USB-C connection is used. Interestingly, our review unit's packaging suggests slightly slower speeds than the manufacturer’s website; there’s a read speed maximum of 2700MB/s and write speeds of up to 1900MB/s.
Boasting an aluminum core designed for efficient heat dissipation, the Pro-G40 SSD is engineered to deliver consistently fast data transfer speeds. This construction also equips it to cope with drops from heights of up to 3m and resist crushing forces of up to 400 lbs. Furthermore, it has an IP68 rating for dust and water resistance, enabling it to withstand submersion at depths of 1.5m for up to 30 minutes. This robust engineering is backed by a 5-year warranty.
SanDisk Pro-G40: Build & Handling
The SanDisk Professional Pro-G40 SSD has a premium quality feel and its sturdy outer shell withstands flexing during heavy-handling. It also emerges unscathed after multiple drops onto a concrete surface.
While its upper surface feels like hard plastic, the edges and underside of the Pro-G40 SSD feature a soft-touch coating that enhances grip and provides a pleasing tactile sensation. However, that coating comes at the expense of collecting fluff.
One minor issue is the length of the supplied Thunderbolt 3 cable. At approximately 15cm (excluding the connectors) it can prove inconvenient when a computer's ports are on its rear. It can also be problematic when using a laptop on your lap. It means the drive may need to rest on the keyboard to prevent slipping and accidental disconnections. However, the cable fits snugly into the drive's port, reducing the likelihood of inadvertent disconnects. Nonetheless, it’s not advisable to hang the drive by its cable.
SanDisk Pro-G40: Performance
Crucially, the SanDisk Professional Pro-G40 mounts promptly, and image thumbnails render very quickly in applications like Adobe Bridge. Impressively, the thumbnails for 200 images (100 JPEGs and 100 raw files) from a 45.7MP Nikon Z7 II were rendered almost instantaneously in Bridge and could be opened in Adobe Camera Raw without delay.
Similarly, the SanDisk Professional Pro-G40 SSD is a very capable working drive for 4K video editing. Its swift data transfer capabilities, coupled with a fast computer, deliver fluid editing with no stuttering or dropped frames. Although the drive warms up during extended usage, it’s not excessive.
When the SanDisk Professional Pro-G40 SSD was connected via Thunderbolt 3 to a 2022 MacBook Air with an M2 chip, the Blackmagic Disk Speed Test measured write speeds of approximately 2800MB/s and read speeds of around 2604MB/s. Those values surpass those listed on the packaging.
In addition, I found that the 200 files from the Nikon Z7 II, which take up 9.74GB, transferred from the MacBook Air's desktop to the drive in approximately 5 seconds. Reversing the transfer direction took a similar amount of time. It means you’re not kept waiting around for your images to shift from one place to another.
To test SanDisk’s water resistance claims for the Pro-G40 SSD, I submerged it in a glass of water with the USB/Thunderbolt port facing upwards. After 30 minutes underwater, the drive was retrieved, dried, and allowed to rest for an additional hour to ensure no lingering water within the port. Post-drying, the drive reconnected seamlessly to a computer and functioned without issue.
SanDisk Pro-G40: Verdict
SanDisk is one of the most widely recognized and respected brands in digital storage, and its Professional line of devices is aimed at professional photographers, videographers, and content creators. Putting the relatively minor inconvenience of the cable length to one side, the SanDisk Professional Pro-G40 SSD matches the expectations of that audience. It has excellent durability, can withstand submersion, and is capable of very fast data transfer.
While its cost might lean towards the higher end of the spectrum, its 5-year warranty and solid performance where it matters make it a worthwhile investment.
August 2023:
Numerous stories are emerging from tech websites and individual users that some SanDisk and WD-branded portable SSDs are experiencing sudden and unpredictable drive failure, resulting in data loss. We have contacted parent company Western Digital for a statement on the issue but have yet to receive a response. In our experience reviewing Sandisk and WD products, we have not had any drives fail, so are publishing reviews as normal until otherwise. However, it is something to be aware of before you decide to purchase any SanDisk or WD-branded portable SSD until the matter has been decisively resolved.
Read more: Find your next storage device with our guides for the best portable SSD. And if you need a computer that can take advantage of this storage then check out our top pick for the best photo-editing laptops.