I don’t know how many small partners have used the PCIe5.0 protocol, but in June 2022, the PCI-SIG working group has officially released the PCIe6.0 protocol. The industry is currently stepping up work to realize the commercial use of the first batch of PCIe6.0 products in 2024. Compared with PCIe5.0, the biggest change in PCIe6.0 is the change in bandwidth and signal modulation method. For example, the maximum bandwidth of PCIe6.0 has doubled to 64GT/s, and the signal modulation method has also been changed from NRZ to PAM4.
PAM4 is four-level pulse amplitude modulation. Compared with NRZ, which only has two levels: 0 and 1, PAM4 has four levels: 0, 1, 2, and 3. Each symbol can carry 2 bits of information. Compared with NRZ, each symbol carries 1 bit of information, which is doubled.
Chip intellectual property (IP) developer Alphawave recently announced that this month it has cooperated with KeySight to test the PCIe6.0 controller, and the data transmission performance has successfully reached the upper limit of 64GT/s.
Alphawave said this shows that the company is ready to build chips that support the PCIe 6.0 protocol, preparing for the arrival of the first commercial PCIe 6.0 devices in 2024.
Alphawave is not the first IP provider to test PCIe6.0-related IP. Another IP provider, Synopsys, has been developing and testing a collection of PCIe6.0-related intellectual property since 2021. This year, the company also demonstrated the interoperability of their PCIe6.0 solution with Intel test chips.
Of course, according to convention, after commercial use in 2024, the price of PCIe 6.0 equipment will definitely be very high. This will take time to slowly advance. For example, the price of PCIe 5.0 products has begun to gradually decline.
Finally, several drafts of PCIe7.0 have been released and are expected to be released in 2025. The single-channel full-duplex bidirectional bandwidth is 16GB/s, the x16 slot can reach 256GB/s, and the bidirectional throughput is 512GB/s, using NVMeS with x4 slots. The SD one-way rate can also reach 64GB/s, which is several times higher than the current PCIe5.0's general maximum rate of 14GB/s. However, this still requires the efforts of SSD controller manufacturers and flash memory chip manufacturers to prepare for 64GB/s transmission.