SanDisk Professional PRO-G40 SSD: 2 Minute Review
Western Digital has divided its product branding into sub-brands, with the SanDisk Professional brand specifically aimed at supporting customers with professional needs.
This group includes external RAID enclosures, desktop G-DRIVE products, and various flash drive readers, as well as external SSDs, which are of interest to us today.
Existing SanDisk customers will be familiar with Extreme PRO portable drives and how they offer the average user excellent value for money. But the SanDisk Professional PRO-G40 isn’t cheap, and it could move from what home users think to business solutions.
There are two aspects to this design that are intended to justify the cost over the Extreme series drives: resilience and performance.
In hand, it’s clear that the PRO-G40’s exterior is much sleeker than the predominantly plastic Extreme PRO offerings. Combining metal foam with a rubberized coating on the bottom and sides, the PRO-G40 offers up to 4000 lbs of impact resistance and the ability to withstand drops of up to 3m.
It’s also rated IP68 for dust and water resistance, so it can handle getting wet and dusty without destroying the drive, but you probably won’t be swimming in it.
SanDisk is so confident that the PRO-G40’s rugged enclosure keeps NAND technology safe inside, and we demonstrate this with our five-year limited warranty.
Ruggedness is a good thing, but the more important selling point here is the performance of this external drive, which rivals some internal SDD storage.
Exact operating speed depends on the speed of the connected system and the connection technology used. The PRO-G40 works with both USB and Thunderbolt interfaces and has the fastest transfer speeds Thunderbolt can achieve.
Performance quoted is 2700MB/s read and 1900MB/s write over Thunderbolt (40Gbps), but drops to nearly 1000MB/s over USB 3.2 Gen 2 (10Gbit).
With Thunderbolt, a 50GB file can be copied to the PRO-G40 in about 30 seconds, provided the internal SSD can keep up.
This performance suggests that if you only have USB 3.2 Gen 2 ports, the SanDisk Extreme Pro, Crucial X8, etc. aren’t worth the extra money. But for those with Thunderbolt 3 or USB 4.0 may be worth the additional investment due to the significant performance improvement.
SanDisk Professional PRO-G40 SSD: Pricing and Availability
- how much does it cost? Starting at $279.99 / £297.99
- When are you coming out? Available now
- where can i get it? Widely available from major online retailers in most regions.
But even for Thunderbolt-connected SSD standards, this cost is expensive, and if you want something more affordable with similar features, you should consider the Plugable range.
I’ve recently noticed a price drop on this drive. This reflects the decreasing cost of NAND modules and increasing competition in this area.
1TB and 2TB models purchased directly from the manufacturer are £297.99 and £495.99 in the UK. Available in the US for $279.99 and $399.99.
As such, it is 20% to 30% higher outside the US.
Prices in other parts of Europe are slightly lower than UK prices, but not by much.
For those wondering how the cost is split between the enclosure and the internal NVMe drives, these drives utilize SN750 SE SSDs. The module is priced at just $95.99 for the 1 TB model.
This puts the PRO-G40 enclosure at over $200 given the retail cost of the modules inside. That’s a price SanDisk rarely pays internally.
That’s double the price of a great USB 3.2 Gen 2 design like the Crucial X8 for the same storage capacity, so it shows that despite recent cost reductions, this is too expensive a product.
SanDisk Professional PRO-G40 SSD: Design
- Rugged housing
- No carrying case
- No USB-A adapter
As an external SSD, the PRO-G40 may not be the smallest we’ve seen, but it feels very sturdy. And while we’ve never driven one on top of ours, it can probably withstand SanDisk’s claimed 4000-pound crash weight.
The rubberized TPU used on the sides and back of the drive keeps other hardware from scratching when placed in the same bag used in laptops.
Out of the box, even at this price, SanDisk doesn’t include a pouch for the drive and USB-C cable, so that’s a good thing. .
The other item missing, which should have actually been included, is a USB-C to USB-A cable.
What you get with this drive is a short 20cm cable that works with both Thunderbolt and USB 3.2 Gen 2 connections, but there’s no way to connect the drive to USB-A, only a USB-C port.
These adapters are not expensive. Crucial includes one free with the X8, and it’s a shame it’s not included in the PRO-G40 box.
I didn’t try to open the review hardware, but there are four visible screws on the top that void the 5-year warranty and for those who want to disable this device’s dust and water resistance. It may help you open it.
SanDisk Professional PRO-G40 SSD: Features
- 1TB and 2TB options only
- No hardware encryption
- Apple formatted
The SanDisk Professional PRO-G40’s biggest drawback is its maximum available capacity of only 2TB. The SanDisk Extreme Series drives come in 500GB and 4TB options, while the PRO-G40 comes in either 1TB or 2TB.
The problem here is that the PRO-G40’s designers apparently decided to make the internal NVMe an SN750 SE, and that’s not included in the 4TB.
A quick scan of Western Digital’s range of retail SSDs reveals that, with the exception of the WD Black SN850X, the largest NVMe drive is 2TB.
Crucial, Sabrent, Corsair, Seagate, and others have created multiple M.2 4TB designs, but more confusingly, SanDisk has a 4TB SSD in its SanDisk Extreme Portable SSD V2 series.
I’m not sure why the PRO-G40 only gets 2TB max, but that’s what you get.
External storage performance is determined by the bandwidth of the onboard NAND module and the configuration of the controller/bridge chip.
In this design, the bridge chip is the Intel Titan Ridge chip, the JHL7440 Thunderbolt 3 controller that first appeared in 2018 and is designed for PCIe Gen 3 operation.
But that silicon doesn’t handle USB, so a secondary Asmedia ASM2362 is used to bridge PCI Express (downstream port) to USB3.1 (UFP).
The JHL7440 has a maximum speed of 40Gbps over Thunderbolt and the Asmedia ASM2362 can transfer 10Gbit/s over USB.
If you purchased the PRO-G40 for an Apple Mac, the drive is pre-formatted with APFS, so all you have to do is take it out of the box and plug it into your Apple-branded computer.
Unfortunately, Microsoft Windows users will find that the drive does not appear when plugged in.
Using the Windows Management Console to delete existing partitions and create new NTFS or exFAT volumes to work requires technical knowledge and confidence.
The choice seems odd because other drive manufacturers offer drives in dual-boot models that allow both Apple and PC owners to configure the drives without requiring any expertise.
SanDisk does not include any kind of software for this drive on the device, and apparently assumes it will only be used with Apple Time Machine on that brand of device.
Also note that the SN750 SE drives used here do not support hardware encryption. While it is possible to use software encryption such as Microsoft BitLocker, it does not provide the same level of protection as hardware encrypted storage.
SanDisk Professional PRO-G40 SSD: Performance
- fast with thunderbolt
- Good speed over USB
Interestingly, when I first saw the PRO-G40, I only tested it on a PC with a Thunderbolt 3 interface, and while it performed well, it wasn’t exceptional.
We’ve seen some external SSDs that support either Thunderbolt or USB 3.2 Gen 2×2, but the increased bandwidth these interfaces offer has a dramatic impact on read and write speeds.
On a Thunderbolt 3 PC, speeds topped out at around 2,770MB/s read and 2,570MB/s write, and on USB-C those numbers dropped to around 1,000MB/s in both directions.
That’s better than SanDisk’s quoted 2700MB/s reading and 1900MB/s, but not as fast as this drive.
When connected to a recent Lenovo ThinkPad Z16 Gen 1 laptop with a USB 4.0 port that is backwards compatible with Thunderbolt 3, the speed has improved significantly.
Through this interface, the PRO-G40 managed over 3,150MB/s read and over 2,700MB/s write using the 2TB model.
This makes the PRO-G40 the fastest external Thunderbolt drive we’ve tested in recent times. The only drive that comes close to this is the OWC Envoy Pro FX, which is even more expensive than the PRO-G40.
The best performance I achieved over USB was around 1,000MB/s both reading and writing, but that’s the interface, not the drive.
The speed of this drive over Thunderbolt may justify the cost in some regions if using Thunderbolt or USB 4.0. , there are cheaper alternatives that match the physical resilience and performance of USB, and can save you a lot of money.
If you want the fastest Thunderbolt external SSD, the PRO-G40 probably has the crown for now.
However, it has a maximum capacity of only 2TB and is cost prohibitive compared to comparable USB devices such as the Corsair X8 and other SanDisk options, making it unattractive.
SanDisk Professional PRO-G40 SSD: Report Card
| worth | Expensive for maximum amount of space | 3/5 |
| design | Elegant design that won’t damage your laptop in the same bag | 4/5 |
| Features | USB and Thunderbolt connectivity. However, USB-A legacy ports are not supported. | 4/5 |
| performance | Significantly faster than Thunderbolt | 5/5 |
| total | Expensive, but probably worth it for those who live by the time is money mantra | 4/5 |
Should I buy the SanDisk Professional PRO-G40 SSD?
