Original Link: https://www.anandtech.com/show/13341/seagate-fast-ssd-and-sandisk-extreme-portable-ssd-1tb-usb-31-das-review
Seagate Fast SSD and SanDisk Extreme Portable SSD 1TB USB 3.1 DAS Review
by Ganesh T S on September 27, 2018 8:00 AM ESTThe advent of 3D TLC flash and high-speed interfaces such as USB 3.1 Gen 2 and Thunderbolt 3 has resulted in a number of economical high-performance direct-attached storage devices in the market. These are essentially SATA or PCIe SSDs behind a SATA - USB 3.1 Gen 2 bridge or a Thunderbolt 3 controller. SATA SSDs behind a USB bridge are budget-friendly. Yet, the performance is quite good for the average consumer workload (particularly those sporting a USB 3.1 Gen 2 bridge). The Seagate Fast SSD and the SanDisk Extreme Portable SSD are two such products targeting the mid-range consumer market.
Introduction
SanDisk / Western Digital has been an active participant in the high-performance external SSD market. The Extreme 500, 510, and 900 series external drives have had excellent market acceptance, and presented a credible alternative to the other external SSDs in the market such as the Samsung T1, T3, and T5 models. The SanDisk Extreme Portable SSD is their latest high-performance external storage device that builds upon the features of the Extreme 510, while addressing some of the minor issues related to the form-factor, connector placement, and thermal throttling.
Seagate's flash-based product portfolio, on the other hand, has had a distinct enterprise focus, along with a few internal consumer SSDs. At the 2018 CES, they announced their first Seagate-branded high-performance external storage device, the Seagate Fast SSD.
The SanDisk Extreme Portable SSD has the same gumstick form-factor as the WD My Passport SSD, thanks to the use of a M.2 2280 SSD internally. However, the casing is rugged, and the internal drive is protected well-enough for the device to carry an IP55 rating for water and dust-resistance.
The 8.85mm x 49.55mm x 96.2mm device weighs just 39 grams. The product is bus-powered. Hence, the supplied material in the package is minimal. In order to ensure wider compatibility, SanDisk also supplies a small Type-C to Type-A adapter along with a 6in. Type-C to Type-C cable. Other than that, we have the usual warranty papers and quick start guide.
The Seagate Fast SSD has a square form-factor, pointing to the use of a traditional 2.5" SSD board. The 9mm x 79mm x 94mm device weighs 82 grams.
Like the SanDisk Extreme Portable SSD, the Fast SSD is also bus-powered. It comes with two 18in. cables - a Type-C to Type-C, and a Type-A to Type-A one. One of the interesting value-additions is the free two months of the Adobe Creative Cloud Photograpy Plan.
Prior to looking at the internals, CrystalDiskInfo provides some insights.
Drive Information |
Both drives support S.M.A.R.T and TRIM across the USB bridge.
Teardown and Internals
The WD My Passport SSD that we reviewed in June 2017 came with a SanDisk X400 (15nm TLC). The Extreme Portable SSD carries a WD Blue 3D NAND SSD (BiCS 64-layer 3D TLC flash) with the Marvell 88SS1074 SSD controller.
We can clearly see the ASMedia ASM235CM acting as a SATA - USB 3.1 Gen 2 bridge chip. Both the main and daughterboards are single-sided and the only thermal protection is a single heat-spreading sticker over the flash packages, SSD controller, DRAM, and the bridge.
The Seagate Fast SSD uses the same board as that of the Seagate BarraCuda SSD launched a few months back. It uses the Toshiba BiCS 64-layer 3D TLC too. The controller, despite the Seagate logo on the package, appears likely to be a re-branded Phison S10 (an educated guess based on the orientation of the controller with respect to the flash packages that we remember seeing in Phison's reference design).
Our teardown shows extensive thermal protection aided by the metal parts of the enclosure. Similar to the SanDisk Extreme Portable SSD, the Fast SSD also has an ASMedia ASM235CM bridge chip on the board.
Usage Impressions
The Seagate Fast SSD and the SanDisk Extreme Portable SSD both come with default volumes formatted in exFAT. We reformatted in NTFS for benchmarking purposes, and to ensure TRIM could get activated.
The SanDisk Extreme Portable SSD comes with the SecureAccess software for password-protecting the drive. On the other hand, the Seagate Fast SSD comes with a link to download the Seagate Toolkit that can set up automatic backup and sync from select folders on the PC to the Fast SSD.
Overall, the usage experience with the drives was largely similar. While the 18in dual-cable package from Seagate comes in handy for wider compatibility with different system setups, the SanDisk 6in. cable with a tag-on Type-C to Type-A adapter is more compact to use and carry around.
Synthetic Benchmarks
Various synthetic benchmarks are available to quickly evaluate the performance of direct-attached storage devices. Real-world performance testing often has to be a customized test. We present both varieties in this review, starting with the synthetic benchmarks in this section. Prior to covering those, we have a quick look at our testbed setup and testing methodology.
Testbed Setup and Testing Methodology
Evaluation of DAS units on Windows is done with the testbed outlined in the table below. For devices with a USB 3.1 Gen 2 Type-C interface (such as the Seagate Fast SSD and the SanDisk Extreme Portable SSD that we are considering today), we utilize the Thunderbolt 3 / USB 3.1 Type-C port enabled by the Intel Alpine Ridge controller. It connects to the Z170 PCH via a PCIe 3.0 x4 link.
AnandTech DAS Testbed Configuration | |
Motherboard | GIGABYTE Z170X-UD5 TH ATX |
CPU | Intel Core i5-6600K |
Memory | G.Skill Ripjaws 4 F4-2133C15-8GRR 32 GB ( 4x 8GB) DDR4-2133 @ 15-15-15-35 |
OS Drive | Samsung SM951 MZVPV256 NVMe 256 GB |
SATA Devices | Corsair Neutron XT SSD 480 GB Intel SSD 730 Series 480 GB |
Add-on Card | None |
Chassis | Cooler Master HAF XB EVO |
PSU | Cooler Master V750 750 W |
OS | Windows 10 Pro x64 |
Thanks to Cooler Master, GIGABYTE, G.Skill and Intel for the build components |
The full details of the reasoning behind choosing the above build components can be found here. The list of DAS units used for comparison purposes is provided below.
- Seagate Fast SSD 1TB
- SanDisk Extreme Portable SSD 1TB
- Samsung Portable SSD T1 1TB - No Encryption
- Samsung Portable SSD T3 2TB
- Samsung Portable SSD T5 2TB
- SanDisk Extreme 900 1.92TB
- WD My Passport SSD 1TB
Synthetic Benchmarks - ATTO and Crystal DiskMark
Seagate and SanDisk both claim read and write speeds of around 540 MBps and 500 MBps respectively, and these are backed up by the ATTO benchmarks provided below. Unfortunately, these access traces are not very common in real-life scenarios.
Drive Performance Benchmarks - CrystalDiskMark |
AnandTech DAS Suite and Performance Consistency
This section looks at how the Seagate Fast SSD and the SanDisk Extreme Portable SSD fare in real-life workloads.
Benchmarks - robocopy and PCMark 8 Storage Bench
Our testing methodology for DAS units also takes into consideration the usual use-case for such devices. The most common usage scenario is transfer of large amounts of photos and videos to and from the unit. The minor usage scenario is importing files directly off the DAS into a multimedia editing program such as Adobe Photoshop.
In order to tackle the first use-case, we created three test folders with the following characteristics:
- Photos: 15.6 GB collection of 4320 photos (RAW as well as JPEGs) in 61 sub-folders
- Videos: 16.1 GB collection of 244 videos (MP4 as well as MOVs) in 6 sub-folders
- BR: 10.7 GB Blu-ray folder structure of the IDT Benchmark Blu-ray (the same that we use in our robocopy tests for NAS systems)
Performance Consistency and Thermal Characteristics |
The Seagate Fast SSD has higher instantaneous transfer rates, and gets done with our workload faster than the SanDisk Extreme Portable SSD. However, while the other drives show consistent performance (unless thermal throttling kicks into place), we see the Fast SSD's write rates drop to the 50 MBps range before recovering at a slightly reduced rate. This shows the SLC cache running out and the drive finding it a bit challenging to recover performance while still trying to keep the host occupied.
On the thermal front, neither SSD has issues with throttling. The Fast SSD lands up at around 52C at the end of our benchmark routine. The SanDisk Extreme Portable is around 65C. The sealed nature and the IP55 rating of the Extreme Portable SSD is a bit of a challenge for cooling, but, the good news is that consumers are unlikely to encounter throttling in day-to-day usage.
Miscellaneous Aspects and Concluding Remarks
The performance consistency for real-world applications was looked at in the previous section. We recently added a test to determine the effectiveness of the thermal solution for sustained workloads. After deleting the SSD volume, a fio workload was set up to write sequential data to the raw drive with a block size of 128K and iodepth of 32 to cover 90% of the drive capacity. The internal temperature, instantaneous write data rate, and total amount of data written in total till that point of time were recorded.
Drive Power Consumption - CrystalDiskMark Workloads |
The Seagate Fast SSD has peaks as high as 5W, while the SanDisk Extreme Portable peaks at 3.4W. The latter is obviously much more power efficient.
The performance of both SSDs is great and as advertised. The Seagate Fast SSD has higher short-term write transfer rates for real-world workloads, but, even a slightly sustained workload involving say, 15 - 20 GB, is likely to be handled in a more consistent manner by the SanDisk Extreme Portable SSD.
Moving on to the pricing aspect, we find Seagate at a disadvantage. The Fast SSD is priced at $280, but the SanDisk model is at $225, and the T5 1TB version is $250. The lack of verical integration might prevent Seagate from competing on price.
The Fast SSD does come with certain value-add features like dead-simple backup and sync software, and the Adobe Creative Cloud subscription. If the Fast SSD and the SanDisk Extreme Portable are within $5 - $10 of each other, the value additions could help tilt the choice in favor of the former. As it stands, the 1TB version of the SanDisk Extreme Portable is very attractively priced at $0.23 / GB. Compared to the Samsung T5, it boasts equivalent performance with a lower price and an IP55 rating. The choice of the SanDisk Extreme Portable is a no-brainer for power users. That said, the Seagate Fast SSD does come out on top in a lot of our typical DAS workloads that involve bursty writes. Some consumers might appreciate that aspect. However, at $280 (compared to SanDisk's $225), it appears to be a tough sell.