| The support for AVX-512 is not "kinda". AVX-512 at the Ice Lake level is supported. The most widespread Intel CPU with AVX-512 support is Tiger Lake and its support is no better than that of Zen 4, it also provides one 512-bit pipeline for FMA or multiplication and two 512-bit pipelines for simple operations, the same as Zen 4. What happens is that Zen 4 has the same execution units as Zen 3, so any program which can keep all the execution units busy is accelerated on Zen 4 only by the greater clock frequency. However Zen 4 has a new frontend for instruction fetching and decoding and for branch prediction. Many programs will be executed more efficiently than on Zen 3, with a better utilization of the execution units, leading to the claimed IPC improvement of 13% on average. Additionally, rewriting a program to use AVX-512 can also improve the utilization of the execution units, leading to a speed-up greater than the clock frequency ratio. Support for a certain ISA does not imply anything about the speed of the CPU, even if sometimes the CPU vendors change in the same generation both the ISA and the microarchitecture, resulting in greater throughput. In this case AMD has postponed the improvement of the execution units for Zen 5. Even if the support for AVX-512 does not improve the maximum possible throughput, it improves the average throughput over many programs. The same is true for most of the Intel CPUs that support AVX-512, except for the top models of server or workstation CPUs, because they have one of the 512-bit FMA units disabled, which results in the same maximum throughput as on Zen 4 or on the older CPUs, since Haswell. |