Arm Cortex-X4, Cortex-A720, and Cortex-A520 and DSU-120
Arm, the renowned semiconductor design company, has recently announced its latest complete platform for mobile computing at the Total Compute Solutions event (TCS23). The focus of this release is on the new generation of Cortex mobile CPU and GPU architecture, which includes the powerful Cortex-X4 mega-core, the high-performance Cortex-A720 large core, and the energy-efficient Cortex-A520 core. This significant update not only marks a shift to a pure 64-bit architecture, leaving behind the 32-bit architecture but also delivers enhanced performance.
The Cortex-X4, Cortex-A720, and other CPU architectures in this release are based on the latest Armv9.2 instruction set, resulting in improved performance and parallelism compared to the previous generation (X2/X3) based on Armv9.0. Moreover, these CPUs can support a wider range of large and extra-large core configurations.
One noteworthy upgrade in this new architecture is the enhanced DynamIQ management core DSU-120. With support for up to 14-core CPUs, the DSU-120 improves CPU parallelism and demonstrates Arm’s readiness for PC notebooks utilizing their technology.
A key change in the architecture is the shift from the previous 1+3+4 configuration to a 1+5+2 setup, allowing more room for powerful cores like the Cortex-A720. This change aligns with the rumors surrounding the Snapdragon 8 Gen3, expected to adopt the 1+5+2 configuration by the end of the year.
With the abandonment of 32-bit architecture, Arm has embraced a pure 64-bit approach, fulfilling a long-awaited transition. This move signifies Arm’s commitment to advancing the performance and capabilities of its processors.
In terms of performance and energy efficiency improvements, the Cortex-X4 mega-core delivers a 15% increase in performance or a 40% reduction in power consumption. The Cortex-A720 large core also achieves a 20% improvement in energy efficiency, while the Cortex-A520 small core exhibits a notable 22% increase in energy efficiency.
As the flagship of single-core performance, the X4 mega-core stands out as the most energy-efficient among Arm’s architectures. It enhances parallelism with an L2 cache that can be boosted to 2MB per core.
The Cortex-A720 large core, which adopts the Armv9.2 instruction set, maintains the same power consumption performance as its predecessor, the A715. Furthermore, architectural optimizations for memory reading significantly reduce power consumption while achieving higher performance than the A78 within the same footprint.
For the Cortex-A520 small core, the primary focus is on low power consumption. By transitioning to a pure 64-bit architecture and reducing the area by 22%, this core achieves an 8% increase in performance.
The entire Cortex-X4, Cortex-A720, and Cortex-A520 family exemplifies improved performance and higher energy efficiency. The X4 mega-core’s 40% reduction in power consumption generates considerable anticipation, while other cores and the DSU demonstrate approximately 20% energy consumption improvements. Overall, the upcoming Snapdragon 8 Gen3 and Dimensity 9300 Series, slated for release later this year, hold great promise based on these advancements from Arm.