Blue Giant IBM in Hot Chips 2025 details the latest Power11 CPU architecture and performance of classic Power Series Server Processors. Add AI acceleration, memory innovation, and 2.5D stacking to achieve higher time lapses.
Power11 CPU architecture is equipped with a large, wide-frequency SIMD engine and focuses on providing end-to-end data bandwidth. Although the previous generation of Power10 CPUs used Samsung 7 nanometers, the new Power11 CPU has not been promoted to 5 nanometers, but has a stronger 7 nanometers, aiming to meet customers' demand for speed rather than density. IBM also expands its cooperation with Samsung. In addition to the process, it also uses Samsung iCube SI Interposer to package it and build a 2.5D stack, which helps optimize and improve power transmission.
According to IBM's statement, the main focus of Power11 CPU is to improve speed and run order strength. It retains a similar structure to the Power10, integrating 16 cores and 160 MB cache memory on a single chip. The number of cores of a dual-slot CPU system can be expanded from 40 to 60, and the tempo speed is also increased from 4.0 GHz to 4.3 GHz. In terms of AI acceleration, each Power11 CPU core has an in-core MMA (multiplexing matrix stacker), while an external ASIC or GPU supports Spyre accelerator. The improvements in these structural layers bring significant performance improvements. Including the performance improvement of small systems up to 50%, the performance improvement of medium systems up to 30%, while the average performance improvement of high-level systems is 14%.
IBM also emphasized that the Power11 CPU has also introduced the Quantum Safe Security function to prepare for the quantum computing era, and this function has also been enabled in the IBM Z large host system. As for memory systems, it is another area where Power11 CPUs bring significant changes. The single slot provides 32 DDR5 ports, which is 4 times more capacity and bandwidth compared to the previous generation of systems equipped with 8 DDR5 ports. IBM also uses a special DIMM shape, which is located under the copper heat dissipator. In addition, IBM's memory system is completely hardware-free, supports DDR4 and DDR5 interfaces, and indicates that DDR5 and DDR6 compatibility may be provided in the future.
Finally, IBM revealed that the next generation of Power series CPUs adopt a triple architecture to create and radiate innovation.