Introduction

ADATA is Taiwan's largest manufacturer of flash storage and DRAM memory for computers. They have been at the forefront of SSD development for many years, bringing us famous SSDs such as the SX8200, SX900, and Gammix S70.



In this review we're taking a look at the ADATA Legend 970, which is the first company's first PCI-Express 5.0 solid-state-drive. We've previously reviewed the Corsair MP700, which came without heatsink, resulting in thermal problems when heavily loaded. The ADATA Legend 970 comes with a heatsink preinstalled—that heatsink even includes a tiny fan to improve airflow. Just like all other "Gen 5" SSDs on the market right now, the ADATA Legend 970 is based on the Phison E26 controller, which is the only controller available at this time with support for the new interface. Other vendors such as Samsung, WD, Kioxia, Silicon Motion and Innogrit are working on their own designs, but have nothing to show yet. For NAND flash the ADATA drive is using Micron's newest B58R 3D TLC NAND with 232-layers. As expected for a high-end drive, a DRAM cache chip is included.

The ADATA Legend 970 is available in capacities of 1 TB ($190) and 2 TB ($330). Endurance for these models is set to 700 TBW and 1400 TBW, respectively. ADATA includes a five-year warranty with the Legend 970 SSD.

Packaging

The Drive

The drive is designed for the M.2 2280 form factor, which makes it 22 mm wide and 80 mm long.


PCI-Express 5.0 x4 is used as the host interface to the rest of the system, which doubles the theoretical bandwidth compared to PCIe 4.0 x4.


In order to power the little fan, an external SATA power is required. It would be much more elegant if ADATA instead pulled power from the drive's own PCB.


On the PCB you'll find the controller and four flash chips, a single DRAM cache chip is included, too.


The heatsink uses thermal tape and four screws to attach to the SSD.

Chip Component Analysis

The Phison PS5026-E26 is Phison's first PCI-Express 5.0 controller. It is the company's current flagship with support for eight flash channels and NVMe 2.0, using an Arm Cortex design. The controller itself is fabricated using a 12 nanometer process at TSMC Taiwan.


The four flash chips are Micron 232-layer 3D TLC NAND. Each chip has a capacity of 512 GB.


One Hynix DDR4-4266 chip provides a total of 4 GB of fast DRAM storage for the controller to store the mapping tables.

Test Setup

Synthetic Testing

• Tests are run with a 20-second-long warm-up time (result recording starts at second 21).
• Between each test, the drive is left idle for 60 seconds, to allow it to flush and reorganize its internal data.
• All write requests contain random, incompressible data.
• Disk cache is flushed between all tests.
• M.2 drives are tested with a fan blowing on them; that is, except for the results investigating uncooled behavior on the thermal testing page.

Real-life Testing

• After initial configuration and installation, a disk image is created; it is used to test every drive.
• Automated updates are disabled for the OS and all programs. This ensures that—for every review—each drive uses the same settings, without interference from previous testing.
• Our disk image consumes around 600 GB—partitions are resized to fill all available space on the drive.
• All drives are filled with random data to 80% of their capacity
• Partitions are properly aligned.
• Disk cache is flushed between all tests.
• In order to minimize random variation, each real-life performance test is run several times, with reboots between tests to minimize the impact of disk cache.
• All application benchmarks run the actual application and do not replay any disk traces.
• Our real-life testing data includes performance numbers for a typical high-performance HDD, using results from a Western Digital WD Black 1 TB 7200 RPM 3.5" SATA. HDDs are significantly slower than SSDs, which is why we're not putting the result in the chart, as that would break the scaling, making the SSDs indistinguishable in comparison. Instead, we've added the HDD performance numbers in the title of each test entry.