Executive Summary

RDNA (Radeon DNA) is a graphics processing unit (GPU) microarchitecture and accompanying instruction set architecture developed by AMD. It is the successor to their Graphics Core Next (GCN) microarchitecture/instruction set. The first product lineup featuring RDNA was the Radeon RX 5000 series of video cards, launched on July 7, 2019. The architecture is also used in mobile products and is manufactured and fabricated with TSMC's N7 FinFET graphics chips used in the Navi series of AMD Radeon graphics cards.

The second iteration of RDNA was first featured in the PlayStation 5 and Xbox Series X/S consoles. Both consoles utilize a custom RDNA 2-based graphics solution as the basis for their GPU microarchitecture. On PC, RDNA 2 is featured in the Radeon RX 6000 series of video cards, which first launched in November 2020. RDNA 2 is also featured in Samsung's Exynos 2200 as the graphics architecture.

The third iteration of RDNA was announced on November 3, 2022, and is featured in the Radeon RX 7000 series of consumer desktop and mobile graphics cards. The fourth and latest iteration of RDNA was unveiled on January 6, 2025, at CES and is used in the Radeon RX 9000 series of desktop graphics cards.

Architecture & Design

RDNA features a new processor design, although the first details released at AMD's Computex keynote hints at aspects from the previous Graphics Core Next (GCN) architecture being present for backwards compatibility purposes. This is especially important for its use (in the form of RDNA 2) in the major ninth generation game consoles (the Xbox Series X/S and PlayStation 5) to preserve native compatibility with their pre-existing eighth generation game libraries designed for GCN.

The architecture features a multi-level cache hierarchy and an improved rendering pipeline, with support for GDDR6 memory. Starting with the architecture itself, one of the biggest changes for RDNA is the width of a wavefront, the fundamental group of work. GCN in all of its iterations was 64 threads wide, meaning 64 threads were bundled together into a single wavefront for execution. RDNA drops this to a native 32 threads wide.

At the same time, AMD has expanded the width of their SIMDs from 16 slots to 32 (aka SIMD32), meaning the size of a wavefront now matches the SIMD size. RDNA also includes a new wave32 dataflow that improves efficiency for more complex code with branches, reduces latency by completing wavefronts faster, and enables using more hardware to execute a workload.

Performance & Thermal

The performance of RDNA-based GPUs has been impressive, with the Radeon RX 5000 series offering competitive performance to NVIDIA's GeForce RTX 20 series. The Radeon RX 6000 series, based on RDNA 2, has also been competitive with NVIDIA's GeForce RTX 30 series.

The Radeon RX 7000 series, based on RDNA 3, has continued this trend, offering competitive performance to NVIDIA's GeForce RTX 40 series. The Radeon RX 9000 series, based on the latest iteration of RDNA, is expected to offer even higher performance and power efficiency.

In terms of thermal performance, RDNA-based GPUs have been designed to operate within a relatively low power envelope, making them suitable for use in a variety of systems, from desktops to laptops. The use of TSMC's N7 FinFET graphics chips has also helped to improve power efficiency and reduce heat generation.

Market Positioning

RDNA has been positioned by AMD as a high-performance, power-efficient GPU microarchitecture, capable of competing with NVIDIA's GeForce GPUs. The architecture has been used in a variety of products, from desktop graphics cards to mobile GPUs, and has been featured in several high-profile consoles, including the PlayStation 5 and Xbox Series X/S.

The success of RDNA has helped AMD to regain market share in the discrete GPU market, and the company has continued to invest in the development of new RDNA-based products. The latest iteration of RDNA is expected to further improve performance and power efficiency, and will likely be used in a variety of upcoming AMD products.

Verdict

In conclusion, RDNA has been a highly successful GPU microarchitecture for AMD, offering competitive performance and power efficiency to NVIDIA's GeForce GPUs. The architecture has been used in a variety of products, from desktop graphics cards to mobile GPUs, and has been featured in several high-profile consoles.

The latest iteration of RDNA is expected to further improve performance and power efficiency, and will likely be used in a variety of upcoming AMD products. As the GPU market continues to evolve, it will be interesting to see how RDNA continues to develop and compete with other architectures.

Overall, RDNA has been a key factor in AMD's success in the discrete GPU market, and will likely continue to play an important role in the company's future products. With its high-performance, power-efficient design, RDNA is well-positioned to remain a competitive force in the GPU market for years to come.