Optical interconnects are crucial for next-generation AI and HPC data centers, but adding them to CPUs and GPUs is complicated, and much of the infrastructure for mass adoption is still lacking. To that end, Intel introduced its first fully integrated optical input/output (I/O) chiplet at the Optical Fiber Communication Conference (OFC) 2024. The optical compute interconnect (OCI) chiplet can be attached to CPUs and GPUs to enable high bandwidth, low power consumption, and extended-reach I/O connectivity.
Intel's OCI chiplet is one of the industry's first fully integrated optical I/O solutions for co-packaging with compute processors. This chiplet supports 64 PCIe 5.0 channels, each transmitting at 32 GT/s in both directions, totaling 4 Tbps, over distances of up to 100 meters using fiber optics. The chiplet uses dense wavelength division multiplexing (DWDM) wavelengths and consumes only five pico-Joules per bit, significantly more energy-efficient than pluggable optical transceiver modules, which consume about 15 pico-Joules per bit, according to Intel.
