SK Hynix is one of the few vertically integrated manufacturers in the flash-based storage market (the others include Samsung, Micron/Investment, Western Digital and Kioxia). The company enjoys a good reputation in the OEM market. A few years ago, they also began exploring direct end-user products. Internal SSD (starting with Gold S31 and Gold P31) is the first to be launched. Late last year, the company launched its first direct-attached storage product, the Beetle X31 portable SSD. In February, a complementary product was launched – the Tube T31 Stick SSD.
The Beetle X31 is a portable SSD with a Type-C upstream port and a separate cable. The Tube T31 is an improvement on the traditional thumb drive, with a Type A male connector. The size of the Beetle X31 makes the use of a bridge solution obvious. Our investigation of the Tube T31 also revealed that the same internal SSD is used, albeit with a different bridge. This review takes a detailed look at the Tube T31, including an analysis of its internals and an assessment of its performance consistency, power consumption and thermal distribution.
Introduction and product impressions
USB flash drives have grown in storage capacity and speed over the past few years. Thanks to the advent of 3D NAND and the rapid iteration of USB specification performance improvements, we now see “stick SSDs” capable of delivering 1GBps+ speeds. Since the launch of Kingston’s DataTraveler Max in late 2021, this segment has been slowly gaining members. Some SSD vendors are even trying to differentiate themselves by offering 2TB SKUs.
The high-performance “stick SSD” segment is relatively new and has been dominated by native UFD controllers (such as the Silicon Motion SM2320 in products like the Kingston DataTraveler Max A and Transcend ESD310C, and the Phison U17 in the OWC Envoy Pro Mini). This is in stark contrast to earlier high-performance UFDs like the Corsair Voyager GTX and Mushkin Ventura Ultra, which employed a SATA SSD controller behind a USB 3.0 bridge. In high-performance scenarios, UFD typically avoids bridging solutions due to thermal constraints. BOM cost is also another important aspect, as UFDs are typically/need to be priced lower than portable SSDs. Factors such as the lack of separate cables help solve this problem, but bridging solutions in the PCB may offset the cost savings.
SK hynix’s Beetle X31 is a traditional portable SSD that uses an SK hynix BC711 M.2 2242 NVMe SSD behind an ASMedia ASM2362 USB 3.2 Gen 2 bridge chip. Unlike other PSSD series that come with multiple capacity options, Beetle X31 is available in only two capacity options – 512GB and 1TB. The reason ended up being the single-chip BC711 internal SSD – a package that integrates the flash chip, SSD controller, and DRAM for the flash translation layer. The highly integrated nature of the BC711 ultimately limits the number of NAND chips and thus capacity options.
The Tube T31 reviewed today also has the same two capacity points – 512GB and 1TB, which suggests the same internal SSD may be used. Integrating the flash chip and controller in a single package alleviates some BOM issues, and the BC711-based bridge-based solution ends up having a similar PCB area to the native UFD controller-based solution.
The Tube T31 is relatively large for a USB flash drive and is bound to interfere with devices/cables connected to adjacent USB ports. However, size is unavoidable due to the use of an M.2 2242 internal SSD and its associated thermal solution. Since this is a UFD solution, the packaging is very simple – only the user manual and the main unit are in an environmentally friendly recyclable box.
The clamshell case design can be easily removed by pushing in the plastic tabs that hold the sides in place so that one pops out and slides off. The circuit board is shielded by a metal cladding, which is held together with the help of three screws and further secured to the circuit board via thermal pads – one on top of the bridge chip in the motherboard and another on the NVMe SSD daughter board.
The internal SSD is a single board with a thin thermal pad on the bottom to stick it to the motherboard.
The single die on the SSD carries the “SK hynix HNB001T14M” package marking – the same marking found in the BC711 M.2 2230 / 2242 OEM NVMe SSD. It uses SK Hynix’s 128L V6 NAND and integrates their internal controller and DRAM.
Unlike the ASMedia ASM2362 used in the Beetle X31, SK hynix chose JMicron’s JMS583 in the Tube T31. The JMicron solution has been around for over 5 years and currently uses the A3 chip (the fourth iteration of the same design, with chip bugs fixed) to improve and resolve system incompatibilities. The bridge appears to be experiencing a resurgence in popularity in the market recently, as evidenced by its use in the Silicon Power PX10 released earlier this year.
The bridge allows SMART pass-through, as shown in the CrystalDiskInfo screenshot below. TRIM is also available, although not explicitly mentioned.
| Smart Passthrough – CrystalDiskInfo | |
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The table below provides a comparative view of the specifications of the different memory bridges presented in this review.
| Direct-attached storage device configuration comparison | ||
| aspect | ||
| downstream port | PCIe 3.0×2 | native flash memory |
| upstream port | USB 3.2 Gen 2 Type A | USB 3.2 Gen 2 Type-C (male) |
| bridge chip | JMicron JMS583-A3 | Huirong SM2320 |
| strength | bus powered | bus powered |
| Use Cases | Lightweight 1GBps stick SSD marketed as thumb drive replacement with focus on performance consistency | 1GBps-rated compact USB thumb drive with retractable cover for Type-C connector |
| physical size | 92.5mm x 30.5mm x 14mm | 82.6mm x 22.3mm x 9.5mm |
| weight | 34 grams | 12.5 grams |
| cable | not applicable | not applicable |
| Smart pass-through | Yes | Yes |
| UASP support | Yes | Yes |
| trim thru | Yes | Yes |
| Hardware encryption | No | not available |
| Evaluate storage | SK Hynix BC711 (SK Hynix V6 128L 3D TLC) | Micron 96L 3D TLC |
| price | $85 100 dollars |
$180 |
| Comment link | SK Hynix Tube T31 1TB Review | Kingston DT Max 1TB review |
An explanation of the test bench setup and evaluation methodology is provided before looking at benchmark data, power consumption, and thermal solution effectiveness.
Test platform setup and evaluation methods
Evaluating direct-attached storage devices (including thumb drives) using the Quartz Canyon NUC (essentially a Xeon/ECC version of the Ghost Canyon NUC) configured with 2x 16GB DDR4-2667 ECC SODIMM and PCIe 3.0 x4 NVMe SSD – IM2P33E8 ADATA 1TB.
The most attractive thing about the Quartz Canyon NUC is that there are two PCIe slots for add-in cards (electrically, x16 and x4). In the absence of a discrete GPU (not required in the DAS testbed), both slots are available. In fact, we also added a spare SanDisk Extreme PRO M.2 NVMe SSD in the CPU-direct M.2 22110 socket on the backplane to avoid DMI bottlenecks when evaluating Thunderbolt 3 devices. This still allows the two add-in cards to run at x8 (x16 electrical) and x4 (x4 electrical). Since the Quartz Canyon NUC does not have native USB 3.2 Gen 2×2 ports, Silverstone’s SST-ECU06 add-in card is installed in the x4 slot. All non-Thunderbolt devices were tested using the Type-C port enabled by the SST-ECU06.
The specifications of the test bench are summarized in the table below:
| AnandTech DAS Testbed Configuration 2021 | |
| system | Intel Quartz Canyon NUC9vXQNX |
| CPU | Intel Xeon E-2286M |
| memory | ADATA Industrial AD4B3200716G22 32GB (2 x 16GB) DDR4-3200 ECC @ 22-22-22-52 |
| operating system driver | ADATA Industrial IM2P33E8 NVMe 1TB |
| Auxiliary drive | SanDisk Extreme PRO M.2 NVMe 3D SSD 1TB |
| add-on card | SilverStone SST-ECU06 USB 3.2 Gen 2×2 Type-C Host |
| operating system | Windows 10 Enterprise x64 (21H1) |
| Thanks to ADATA, Intel and SilverStone Tek for providing the build components | |
Test bench hardware is only one part of the evaluation. Typical direct-attached storage workloads for memory cards have also changed over the past few years. High bitrate 4K video at 60fps is already quite common, and 8K video is also starting to appear. Thanks to high-resolution textures and artwork, game installation sizes have steadily grown even on portable consoles. Keeping this in mind, our evaluation scenario for portable SSDs and UFDs involves multiple workloads, which are described in detail in the corresponding sections.
- Synthetic workload using CrystalDiskMark and ATTO
- Real-world access tracking using the PCMark 10 Storage Benchmark
- Custom robocopy workload reflecting typical DAS usage
- Sequential write stress test
In the next section, we’ll provide an overview of the SK hynix Tube T31’s performance on these benchmarks. Before providing conclusions, we also made some observations on SSD power consumption data and thermal solutions.