After years of continued innovation in PCIe's bandwidth, we've hit somewhat of a snag in recent times; after all, the PCIe 3.0 specification has been doing the rounds on our motherboards ever since 2010. PCI-SIG, the 750-member strong organization that's in charge of designing the specifications for the PCIe bus, attribute part of this delay to industry stagnation: PCIe 3.0 has simply been more than enough, bandwidth-wise, for many generations of hardware now. Only recently, with innovations in storage mediums and innovative memory solutions, such as NVMe SSDs and Intel's Optane, are we starting to hit the ceiling on what PCIe 3.0 offers. Add to that the increased workload and bandwidth requirements of the AI field, and the industry now seems to be eager for an upgrade, with some IP vendors even having put out PCIe 4.0-supporting controllers and PHYs into their next-generation products already - although at the incomplete 0.9 revision.