The Phison PS5016-E16 will be the first commercially available SSD to utilize the PCI Express 4.0 specification. The new bus will double lane throughput and usher in new devices with increased performance capabilities or have the ability to operate on fewer lanes while utilizing less power.
Like the transition from SATA 3Gbps to 6Gbps and PCIe 2.0 to 3.0, some areas of performance will instantly increase while others will take time to mature. This isn't limited to just storage devices but all new components
For storage devices, the bus interface isn't the bottleneck for small block size random performance. Core architecture improvements required to maximize large block size throughput will have a moderate impact on random workloads. To see large gains in random latency, we will have to wait for the next-generation flash to lower transaction times between the controller and the memory, the link on the other side of the controller.
Today we will look at the new Phison PS5016-E16 controller and a 2TB reference design that should be very close to the early models coming to market from companies that have already announced E16 products. To date, Corsair, GIGABYTE, Galax, and PNY displayed E16 products at Computex. Other companies with strong ties to Phison have yet to make announcements, mainly MyDigitalSSD and Kingston/HyperX.
AMD has yet to release the highly anticipated X570 chipset and accompanying processor that ushers in the PCI Express 4.0 era. Without hardware in hand, or even an NDA date to break (just kidding), we will use our existing PCIe 3.0 platform to test the drive. Our current platform is closer to what most shoppers still use. We can say that no one has PCI Express 4.0 today other than a handful of servers running IBM architecture without Windows support.
The Phison E16 controller uses dual ARM Cortex5 processors with a CoXprocessor built on TSMC's 28nm process. This is the similar layout as Phison's PS5012-E12 controller with an 8-channel design with 32 chip enables. The modular design allowed the company to change the front end PHY to support the PCI Express 4.0 standard while still utilizing the same NVMe 1.3 protocol of the previous generation.
Phison's generic specifications claim sequential read performance of 5,000 MB's. Sequential write performance reaches up to 4,400 MB/s. Random performance peaks at 750,000 IOPS read and up to 700,000 IOPS write.
To reach these speeds the E16 controller requires massive parallelization from the flash memory. With current die sizes, the smallest capacity E16 SSD comes from a 512GB base memory product. Some companies may choose to use overprovisioning to increase performance but drop the user capacity to 480GB or 500GB. This is a radical shift from all previous generation products with 256GB and even 128GB models.
The larger capacities and first of its kind design means the retail E16 SSDs will likely carry premium pricing. Phison originally listed availability at Q4 2019 but invested an additional 12 million dollars to reel in the date to coincide with AMD's Ryzen 3000 Series launch.
A Closer Look
Most of the E16 models on display at Computex were fitted with heat sinks. There were only a few images of naked drives, like our reference design sample.
We expect this layout to be the same as early retail products. We expect the companies that already announced E16-based SSDs to ship when AMD's Ryzen 3000 comes to market. Some companies may get a jump and release drives earlier.
The layout is nearly identical to the previous generation E12 drives we've tested. For the most part, the E16 looks like a drop-in replacement for the reference design board. The sole difference on the outside is the new nickel plate that acts as a heat sink for the controller.