The push by AMD into PCI Express 4.0 territory with its Ryzen 3000 series processors and X570 chipset is leading to faster SSDs, but to quote Randy Bachman's lyrics, you ain't seen nothing yet. Phison says we'll see SSDs hitting 6.5GB/s (or 6,500MB/s) in 2020.
If you haven't been following, AMD is the first to make use of the PCIe 4.0 bus spec, which doubles the bandwidth of PCIe 3.0 that is found on every modern motherboard currently shipping. It's already been usurped on a technical level by PCIe 5.0, which was only recently ratified, but it will be several years before we see any actual PCIe 5.0 products.
The same is not true of PCIe 4.0. Several companies have already announced PCIe 4.0 SSDs, all of which use a Phison PS5016-E16 controller. These new SSDs boast sequential read speeds of around 5GB/s. In contrast, the best NVMe SSDs typically top out read performance at 3.5GB/s.
Phison is already looking past its PS5016-E16 controller and is working on a new one that will support even faster speeds. Mixed Skills (via Overclock3D) posted a video to YouTube that shows Phison CEO K.S. Pua saying the new controller is "coming in Q1 next year," enabling reads of up to 6.5GB/s.
On the technical side, PCIe 4.0 supports around 2GB/s per lane, so in a x4 configuration, the bandwidth ceiling sits at roughly 8GB/s. That is the theoretical limit and doesn't account for overhead. Still, there is headroom to venture into the kind of territory that Phison is promising.
Incredibly fast read speeds won't have any noticeable impact on gaming, compared to existing SSDs. But for transferring lots of large files, faster drives can speed things up. Just as importantly, though, faster SSDs could help drive down pricing of today's models. We have already seen this to some extent, with NVMe SSDs becoming more affordable in the past few months.
That said, just because a controller supporting 6.5GB/s read speeds will soon exist doesn't mean that SSDs will immediately follow. It may take some time for SSD makers to employ the new controller. However, given that Phison is aiming for a first-quarter release, it's to expect that faster SSDs will follow sometime in 2020.