Zen 5 Crushes Zen 4: 40% AVX-512 Performance Boost
Recent leaks have suggested that the Zen 5 core outpaces the Zen 4 by 40%, a figure attributed to Zen 5’s performance enhancement over Zen 4 in benchmark tests utilizing AVX-512 instructions. Although this improvement does not stem from an IPC (Instructions Per Cycle) increase, a 40% enhancement through AVX-512 is indeed remarkable.
The substantial uplift in AVX-512 performance for Zen 5, as explained by Moore’s Law is Dead, is due to its possession of a true 512-bit FPU (Floating Point Unit). Currently, the Zen 4 architecture executes AVX-512 operations using two 256-bit FPUs. However, with a 512-bit FPU, Zen 5 can achieve superior performance in computing AVX-512 and VNNI instructions among other AI workloads. This approach to AVX-512 support has been implemented by Intel for some time now, with its 12th to 14th generation Core processors featuring AVX-512 and AMX units within the P-Cores. However, due to the hybrid architecture, these capabilities have not been made accessible to users.
Equipping Zen 5 with a 512-bit FPU necessitates the expansion of other supporting infrastructure, including components that supply data and instructions to the FPU. This is because Zen 5 has increased the L1 DTLB capacity and broadened the load/store queues to meet the demands of the new FPU. The L1 data cache has been expanded from 32KB to 48KB, a 50% increase, enhancing the core’s efficiency in reading and writing data, thereby boosting performance. The FPU MADD latency has been reduced by one cycle, increasing responsiveness and accelerating floating-point operations and data processing speeds. Furthermore, AMD has increased the number of integer execution pipelines in Zen 5 from eight in Zen 4 to ten, enhancing the overall computational performance of each core, while the size of the L2 cache per core remains at 1MB.
AMD is likely to reveal more information about Zen 5 at this year’s Taipei Computer Expo, and processors utilizing the Zen 5 architecture, potentially the Ryzen 9000 series, are highly anticipated to be launched and introduced to the public within the year.
