PCI EXPRESS 5.0
Alder Lake will be the first consumer platform to support PCIe Gen5 devices, but actual support may vary by motherboard and processor. We know that most
Z690 motherboards theoretically have support for PCIe Gen5, but we don’t have the hardware to test that support just yet. Both the latest graphics cards and the latest M.2 SSDs are still sitting in Gen4 land, but we should see Gen5 SSDs at least arrive this year.
One thing we don’t expect is widespread support for PCIe
Gen5 on laptops. In fact, right now most shipping laptops are still using PCIe Gen3 SSDs because the minor gains in normal workloads from a faster Gen4 SSD don’t measure up to the increased power requirements and loss of battery life.
It’s an interesting change in position for Intel, after being late to the PCIe Gen4 party—support for that only arrived with Rocket Lake and Z590 processors and chipsets. AMD already supported Gen4 with its Zen 2 Ryzen 3000 processors, launched in 2019, two years ahead of Intel’s 11th Gen CPUs. Now Intel is ahead of AMD, as well as Nvidia and the various SSD providers. Most people won’t need that doubled bandwidth any time soon, but it will be beneficial in the data center.
Also note that Intel doubled the speed of the DMI interface between the chipset and the CPU with Alder Lake. It’s basically the equivalent of a PCIe Gen4 x8 interface now, double the bandwidth of the DMI 3.0 x8 interface on Rocket Lake and quadruple the bandwidth on Comet Lake and earlier chips. That wider interface means motherboards can hang more Gen4 M.2 slots off the PCH and still have full performance on any attached SSDs.