Where are the PCIe 5.0 SSDs, despite indications from AMD and leading controller chip maker Phison that the drives will be available in November to coincide with AMD's 5th generation compatible Ryzen 7000 series CPUs, the faster 5th generation M.2 model is nowhere to be found. The lack of news about the drives suggests that 5th generation storage is unlikely to appear this year.

Phison is an authority on SSD technology as the SSD industry's leading third-party supplier of controller chips. The company's controller chips have become by far the most popular choice among vendors who do not have the massive technological clout necessary to tape out their own chips; in May, Phison announced the E26 controller for the 5th generation, and in October, Phison announced that "AMD's AM5 platform and Ryzen 7000 series CPUs to the market, we expect 5th generation drives to be available by the end of this year" (opens in new tab).

Now, almost a month after the release of the Ryzen 7000 chips, not a single 5th generation drive has been released. This includes major players such as Samsung and Micron, which have the resources to develop their own controller chips. These brands have also yet to announce a 5th generation drive. [Unlike AMD's latest desktop platforms, however, Intel does not offer a dedicated quad-link PCIe Gen 5 interface to the CPU socket for storage. [Instead, enabling Gen 5 storage on Intel platforms requires splitting the 16-lane graphics link in two, freeing up eight lanes for PCIe Gen 5 drives that connect via an add-in card rather than an M.2 slot on the motherboard.

In any case, the larger question is whether Gen 5 SSDs offer any real significant advantages. In theory, Gen 5 doubles the theoretical bandwidth of quad-link drives to 16 GB/s in both directions. In practice, the fastest Gen 4 drives are limited to about 7.3 GB/s due to I/O overhead, so just under 15 GB/s may be a realistic expectation for Gen 5 drives.

More to the point, what needs the most improvement in existing SSDs is arguably not peak sequential performance, but 4K random access and IOPS throughput. Current high-end Gen 4 drives are limited by these metrics to around 300 MB/s, far from the maximum bandwidth of the Gen 4 interface. Doubling the headroom will make no difference in this. Instead, the IOPS performance of the controller chip is obviously important, but what is primarily needed are improvements in flash memory technology.

At any rate, we don't expect to see a quantum leap in 4K random access performance in the first round of PCIe Gen 5 drives. Therefore, the delay in launch is probably not that significant.