SanDisk Professional PRO-G40 Thunderbolt / USB Dual-Mode Portable SSD Reviewby Ganesh T S on October 6, 2022 8:00 AM EST
Synthetic Benchmarks - ATTO and CrystalDiskMark
Benchmarks such as ATTO and CrystalDiskMark help provide a quick look at the performance of the direct-attached storage device. The results translate to the instantaneous performance numbers that consumers can expect for specific workloads, but do not account for changes in behavior when the unit is subject to long-term conditioning and/or thermal throttling. Yet another use of these synthetic benchmarks is the ability to gather information regarding support for specific storage device features that affect performance.
Western Digital claims read and write speeds of 2700 MBps and 1900 MBps respectively, and these are backed up by the ATTO benchmarks provided below. In fact, WD has been quite conservative in their claims, and has actually put in numbers that are more representative of sustained usage for the PRO-G40's use-case. ATTO benchmarking is restricted to a single configuration in terms of queue depth, and is only representative of a small sub-set of real-world workloads. It does allow the visualization of change in transfer rates as the I/O size changes, with optimal performance being reached around 1 MB for a queue depth of 4. The effect of enabling write caching are also evident at higher I/O sizes, with the feature enabling better consistency.
CrystalDiskMark. for example, uses four different access traces for reads and writes over a configurable region size. Two of the traces are sequential accesses, while two are 4K random accesses. Internally, CrystalDiskMark uses the Microsoft DiskSpd storage testing tool. The 'Seq128K Q32T1' sequential traces use 128K block size with a queue depth of 32 from a single thread, while the '4K Q32T16' one does random 4K accesses with the same queue configuration, but from multiple threads. The 'Seq1M' traces use a 1MiB block size. The plain 'Rnd4K' one uses only a single queue and single thread . Comparing the '4K Q32T16' and '4K Q1T1' numbers can quickly tell us whether the storage device supports NCQ (native command queuing) / UASP (USB-attached SCSI protocol). If the numbers for the two access traces are in the same ballpark, NCQ / UASP is not supported. This assumes that the host port / drivers on the PC support UASP.
The 32GB data span used in our portable SSD reviews fits in nicely with the amount of SLC cache present in the PRO-G40 (as we shall see further down in this review). Read and write numbers are well beyond the advertised values, and the performance scales with the host interface - acting as a 1GBps-class drive with non-Thunderbolt ports, and as a 2.5GBps+ drive when connected to a Thunderbolt 3 host.
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Chaitanya - Thursday, October 6, 2022 - linkWD are mudding the waters a lot with far too many products and far too many occurrences of bait and switch for SKUs. Seems like for now Samsung and Seagate remain "safe" options.
hubick - Friday, October 7, 2022 - linkThis is nothing new over the LaCie Rugged SSD Pro I got back in 2020. When are we gonna see an integrated Thunderbolt/USB4 + flash controller, like the Silicon Motion SM2320 is for USB 2x2?
schmadde - Saturday, November 5, 2022 - linkMore competition will eventually lead to lower prices - at least I hope so.
According to this test the Sandisk is significantly faster than the LaCie, though.
R3MF - Friday, October 7, 2022 - linkI mean, it's lovely that they have made this product, but literally the only thing i want to see from WD's protable drive division is a USB4 product that can do full drive capacity writes at speeds greater than that achievable by USB 3.2x2.
Make me one of those.
Exotica - Friday, October 7, 2022 - linkIt’s better to just get a better performing drive such as a sn770 or sn850 or Samsung 980 pro and slap it in a thunderbolt enclosure, such as that made by Acasis, and you will get excellent performance. I’ve been doing this for a couple years now…
hubick - Friday, October 7, 2022 - linkLast I checked there were no enclosures that had USB fallback compatibility though?
shanti_shakti - Sunday, October 9, 2022 - linkThere are many such TB3/USB fallback enclosures available, and they have been available for a long time.
I’ve using a couple from ‘Acasis’ for around a year now, with Samsung 980 Pro drives inside. Work perfectly via TB3 and USB.
schmadde - Saturday, November 5, 2022 - linkWould you name the "many" TB+USB enclosures? I only know a handful of TB enclosures and most of them are either slow (sometimes only 2 PCIe lanes connected) or don't have USB Fallback and all of them are quite expensive, so the price difference to the sandisk is not huge at least for 1 TB and if you match it with an SSD that is as fast probably negligible.
The Acasis/Delock I have myself and it has compatibility issues. My 970 Evo Plus while quite fast inside a computer is very slow in the Acasis case.
I just checked prices: the USD prices listed in the article look o.k., but the EU prices are outrageous. The 1 TB drive is as much over here as the 2 TB in the US. For this price they can keep it
Techie2 - Monday, October 10, 2022 - linkWhat I want to know is where are all of those Gen 5 internal SSDs that were suppose to be available for purchase in Oct. '22? What a crock to promote products that can't be purchased.
Ryan Smith - Tuesday, October 11, 2022 - linkThey will not be available until November.
As far as I can recall, this was always the plan; no one announced availability for October.