AMD Radeon 820M vs AMD Radeon RX 7900M Comparison

Head-to-Head Benchmarks

The comparison between the AMD Radeon 820M and the AMD Radeon RX 7900M is defined by an overwhelming performance gap. The RX 7900M holds an average benchmark score of 97,487 across recorded tests, while the 820M has no recorded benchmark scores in the database. This absence of data for the 820M means that every measurable performance metric in this comparison belongs exclusively to the RX 7900M.

In the 3DMark Steel Nomad DX12 test, the RX 7900M records a score of 4,201. This test stresses modern DirectX 12 workloads, and the result places the RX 7900M in a strong position for contemporary gaming and compute tasks. The 820M, lacking any recorded score in this test, offers no comparable dataset.

The Geekbench OpenCL test shows the RX 7900M achieving 129,499 points. OpenCL performance is relevant for general-purpose GPU compute, including rendering, physics simulations, and data processing. The RX 7900M's score here indicates substantial compute throughput, far beyond what an integrated graphics processor with 128 shading units could plausibly deliver.

In the Geekbench Vulkan test, the RX 7900M scores 158,760 points. Vulkan is a low-overhead graphics API widely used in gaming and professional applications. This result represents the highest single-score entry in the RX 7900M's recorded benchmarks, confirming its strength in Vulkan-based workloads.

The percentile ranking reinforces the separation. The RX 7900M sits at the 94th percentile among all GPUs in the database, meaning it outperforms 94% of all recorded graphics processors. The 820M, with a percentile ranking of 50, sits exactly at the median. However, this percentile for the 820M is computed without any benchmark scores, so it reflects a default position rather than measured performance.

The RX 7900M's nearest rivals in the database provide additional context. The AMD Radeon Pro VII scores 97,131, which is just 0.4% below the RX 7900M. The NVIDIA Quadro RTX 6000 scores 101,872, which is 4.3% higher. The AMD Radeon Instinct MI60 scores 92,466, which is 5.4% lower. The NVIDIA RTX A4500 scores 91,671, which is 6.3% lower. These deltas show that the RX 7900M sits comfortably among professional-grade workstation GPUs, trading blows with cards designed for high-end rendering and compute.

The Verdict

The data in the database points to one unambiguous conclusion: the AMD Radeon RX 7900M is in a completely different performance class than the AMD Radeon 820M. With an average benchmark score of 97,487 and a 94th percentile ranking, the RX 7900M is a high-end mobile discrete GPU. The 820M, with no recorded benchmarks and a 50th percentile default, is an entry-level integrated graphics solution.

Users who need serious graphics performance, whether for gaming, 3D rendering, or GPU compute, should choose the RX 7900M based on the benchmark evidence. The 4,201 Steel Nomad score, 129,499 OpenCL result, and 158,760 Vulkan score all demonstrate capable performance across multiple API environments. The RX 7900M also holds its own against professional workstation cards, as shown by its near-parity with the Radeon Pro VII and its lead over the Radeon Instinct MI60 and RTX A4500.

The 820M is appropriate for systems where graphics demands are minimal and power efficiency is paramount. Its 15 W TDP, compared to the RX 7900M's 180 W TDP, indicates a dramatically lower power draw. The 820M's integrated design means it shares system memory and produces no additional cooling requirements beyond the host laptop's chassis. For basic display output, office productivity, and lightweight media playback, the 820M suffices. For anything demanding, the RX 7900M is the only choice supported by the recorded data.

Architecture Differences

The two GPUs come from different generations of AMD's RDNA architecture. The RX 7900M uses RDNA 3.0, built on a 5 nm process at TSMC. It features the Navi 31 chip, codenamed Plum Bonito, and belongs to the Navi Mobile (RX 7000M) generation. The 820M uses RDNA 3.5, built on a 4 nm process at TSMC. It features the Krackan Point 2 chip and belongs to the Navi III IGP (Strix Point Mobile) generation.

The process node difference is notable: 5 nm for the RX 7900M versus 4 nm for the 820M. The 820M uses a more advanced manufacturing process, which typically enables higher transistor density and better power efficiency per unit of compute. However, the RX 7900M's chip is vastly larger and more complex. The Navi 31 chip contains 57,700 million transistors on a 529 mm² die, with a transistor density of 109.1 million per mm². The 820M's transistor count and die size are listed as unknown in the database.

The ray tracing capabilities differ substantially. The RX 7900M has 72 ray tracing cores, while the 820M has only 2. This 36-fold difference in ray tracing hardware means the RX 7900M can handle hardware-accelerated ray tracing workloads with far greater throughput. Both GPUs support DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4, so API compatibility is identical.

The RX 7900M's predecessor is Polaris Mobile, while the 820M's predecessor is Navi II IGP. Both are currently active in production status. The RX 7900M was released on 2023-10-18, while the 820M was released on 2025-02-28, making the 820M a significantly newer product by release date.

Specification Differences

The RX 7900M and 820M differ across nearly every measurable specification. The most fundamental difference is the compute unit configuration. The RX 7900M has 4,608 shading units, 288 texture mapping units, and 192 raster operation units. The 820M has 128 shading units, 8 TMUs, and 4 ROPs. These numbers represent a 36x difference in shading units, a 36x difference in TMUs, and a 48x difference in ROPs.

Clock speeds also diverge significantly. The RX 7900M has a base clock of 1,825 MHz and a boost clock of 2,090 MHz. The 820M has a base clock of 400 MHz and a boost clock of 2,800 MHz. The 820M's boost clock is notably higher, but its massively smaller compute configuration means that higher clock speed cannot compensate for the core count disparity.

Memory specifications are entirely different. The RX 7900M has 16 GB of GDDR6 memory on a 256-bit bus, with a memory clock of 2,250 MHz (18 Gbps effective) and a bandwidth of 576.0 GB/s. The 820M uses system-shared memory with a system-dependent bandwidth. This means the RX 7900M has dedicated, high-bandwidth VRAM, while the 820M relies on the host system's main memory.

Rasterization and texture throughput numbers illustrate the performance gap. The RX 7900M achieves a pixel rate of 401.3 GPixel/s and a texture rate of 601.9 GTexel/s. The 820M achieves 11.20 GPixel/s and 22.40 GTexel/s, respectively. The RX 7900M's pixel rate is roughly 36x higher, and its texture rate is roughly 27x higher.

Compute throughput follows the same pattern. The RX 7900M delivers 38.52 TFLOPS of FP32 performance and 77.05 TFLOPS of FP16 performance (at a 2:1 ratio). The 820M delivers 716.8 GFLOPS of FP32 and 716.8 GFLOPS of FP16 (at a 1:1 ratio). The RX 7900M has roughly 54x the FP32 throughput.

Power consumption is a major differentiator. The RX 7900M has a TDP of 180 W, while the 820M has a TDP of 15 W. The RX 7900M uses a PCIe 4.0 x16 interface, while the 820M uses PCIe 4.0 x8. Both are listed as IGP slot width with no power connectors and portable-device-dependent display outputs.

FAQ

Q: Which GPU has a higher average benchmark score?

A: The AMD Radeon RX 7900M has an average benchmark score of 97,487. The AMD Radeon 820M has no recorded benchmark scores in the database.

Q: How does the RX 7900M compare to its nearest rivals?

A: The RX 7900M scores 0.4% higher than the AMD Radeon Pro VII, 4.3% lower than the NVIDIA Quadro RTX 6000, 5.4% higher than the AMD Radeon Instinct MI60, and 6.3% higher than the NVIDIA RTX A4500.

Q: What is the memory configuration difference?

A: The RX 7900M has 16 GB of GDDR6 memory on a 256-bit bus with 576.0 GB/s bandwidth. The 820M uses system-shared memory with system-dependent bandwidth.

Q: Which GPU has more shading units?

A: The RX 7900M has 4,608 shading units, while the 820M has 128 shading units, a 36-fold difference.

Q: What is the TDP difference between the two?

A: The RX 7900M has a TDP of 180 W, while the 820M has a TDP of 15 W.

Q: Which GPU supports hardware ray tracing?

A: Both support ray tracing, but the RX 7900M has 72 ray tracing cores, while the 820M has only 2.

Where Each One Wins

The RX 7900M wins in every recorded benchmark category. Its 4,201 score in 3DMark Steel Nomad DX12 indicates strong performance in modern DirectX 12 gaming workloads. Its 129,499 Geekbench OpenCL score shows capability in general-purpose compute tasks. Its 158,760 Geekbench Vulkan score demonstrates excellent performance in Vulkan-based applications, which include many contemporary game engines and professional visualization tools.

The RX 7900M's 94th percentile ranking places it above the vast majority of GPUs in the database. Its nearest rival comparisons show it performing within 4.3% of the NVIDIA Quadro RTX 6000, a professional workstation card, and ahead of the Radeon Pro VII, Radeon Instinct MI60, and RTX A4500. This positions the RX 7900M as a viable option for demanding workloads that would traditionally require workstation-class hardware.

The 820M, with no recorded benchmarks, has no measurable wins in the database. Its advantages are qualitative and structural. The 15 W TDP makes it suitable for thin-and-light laptops where power budgets are tight. The 4 nm process node represents a more advanced manufacturing technology than the RX 7900M's 5 nm node. The 2,800 MHz boost clock is higher than the RX 7900M's 2,090 MHz boost clock, though this is irrelevant given the massive core count disadvantage.

The 820M's PCIe 4.0 x8 interface, while narrower than the RX 7900M's x16 interface, is sufficient for its integrated design. The system-shared memory architecture eliminates the need for dedicated VRAM, reducing cost and complexity in the host system. The 820M supports the same DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4 APIs as the RX 7900M, so software compatibility is not a differentiator.

For use cases, the RX 7900M is the clear choice for high-refresh-rate gaming, 3D rendering, video editing, and GPU-accelerated compute. The 820M is suited for basic productivity, web browsing, and media consumption. The recorded data provides no scenario where the 820M outperforms the RX 7900M. The RX 7900M dominates every measurable aspect of graphics performance, while the 820M offers efficiency and simplicity in exchange for vastly reduced capability.