But it doesn't stop there; the PCI-SIG just announced that the PCIe 6.0 specification has now been moved up to Revision 0.3 and is on track to be finalized in 2021. With the PCIe 6.0 spec, we'll see bandwidth double once again (compared to PCIe 5.0) to 256GB/sec with an x16 slot.
PCI-SIG says that it is able to achieve this incredible ramp up in bandwidth primarily thanks to two updates to the specification. The first is quad-level Pulse Amplitude Modulation (PAM-4), while the second refers to Forward Error Correction (FEC).
Considering the rather lengthy period of time between PCIe 3.0 and PCIe 4.0 specifications -- the former was certified in 2010, while the latter received its certification in 2017, with the first devices shipping two years later -- PCI-SIG is understandably trying to pick up the pace PCIe 5.0 and subsequently PCIe 6.0.
So, what does all of those mean for enthusiasts for the time being? Not much at this point. Only AMD has embraced PCIe 4.0 at this time, and Intel's first PCIe 4.0 compatible chipsets aren't expected to arrive until the latter half of 2020. PCIe 5.0 products are even further out still, and we may not even see the first shipping PCIe 6.0 components arrive until 2023 at the latest.
By that time, who knows what kind of incredibly powerful GPUs will be on tap from AMD, NVIDIA, and Intel to feed the beast... not to mention future SSDs. However, the biggest benefactors of PCIe 5.0 and PCIe 6.0 will like be in the data center market for high-end artificial intelligence and machine learning workloads.