AMD Radeon 820M vs AMD Radeon RX 7800M Comparison

FAQ

Q: What are the core architectural differences between the AMD Radeon 820M and the AMD Radeon RX 7800M?

A: The Radeon 820M uses the Krackan Point 2 chip built on TSMC's 4 nm process with RDNA 3.5 architecture, while the Radeon RX 7800M uses the Navi 32 chip on a 5 nm process with RDNA 3.0 architecture. The RX 7800M has 28,100 million transistors on a 346 mm² die, whereas the 820M's transistor count and die size are not recorded in the database.

Q: How do their memory configurations compare?

A: The Radeon 820M uses system shared memory with a system-dependent bus width and bandwidth, while the Radeon RX 7800M has 12 GB of dedicated GDDR6 memory on a 192-bit bus delivering 432.0 GB/s bandwidth. The RX 7800M's memory clock is 2250 MHz with 18 Gbps effective speed.

Q: Which GPU has higher raw compute throughput?

A: The Radeon RX 7800M delivers 35.87 TFLOPS FP32 performance with 3840 shading units, 240 texture mapping units, and 96 render output units. The Radeon 820M provides 716.8 GFLOPS FP32 with 128 shading units, 8 TMUs, and 4 ROPs.

Q: What is the performance rating difference in the database?

A: The Radeon RX 7800M sits at the 73rd percentile among all GPUs with an average benchmark score of 27883, while the Radeon 820M holds the 50th percentile with an average score of 0 in the recorded data. The RX 7800M's nearest rivals are within 0.8% of its score.

Q: Do both GPUs support the same graphics APIs?

A: Yes, both support DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. However, the RX 7800M has 60 ray tracing cores compared to the 820M's 2 RT cores.

Q: What are the clock speed differences between the two?

A: The Radeon 820M has a base clock of 400 MHz and boost clock of 2800 MHz, while the Radeon RX 7800M runs at 1295 MHz base, 2145 MHz game clock, and 2335 MHz boost. The RX 7800M has a significantly higher base clock despite the 820M's higher boost frequency.

Where Each One Wins

The Radeon 820M wins in the integrated graphics category. It is an IGP with a 15 W TDP, requires no power connectors, and uses system shared memory. This makes it suitable for portable devices where power efficiency and space constraints dominate. The 820M also uses a newer 4 nm process node and RDNA 3.5 architecture, which indicates a more recent design generation.

The Radeon RX 7800M wins decisively in raw performance and dedicated graphics capability. It has 12 GB of dedicated GDDR6 memory, a 192-bit memory bus, and 432.0 GB/s of bandwidth. Its compute resources are substantially larger: 3840 shading units versus 128, 240 TMUs versus 8, and 96 ROPs versus 4. The RX 7800M also has 60 ray tracing cores compared to just 2 on the 820M. Its 180 W TDP reflects a much higher performance envelope.

The RX 7800M's benchmark record shows strong results across multiple tests. It scores 2994 in 3DMark Steel Nomad DX12, 120778 in Geekbench OpenCL, and 126668 in Geekbench Vulkan. Passmark results include 17613 in G3D, 9342 in GPU Compute, and 892 in G2D. The 820M has no recorded benchmark scores in the database, so the measured wins all belong to the RX 7800M.

Architecture Differences

The two GPUs represent different architectural generations and design philosophies. The Radeon 820M uses RDNA 3.5 on a 4 nm TSMC process, which is the newer manufacturing technology. Its chip is designated Krackan Point 2 and belongs to the Navi III IGP generation for Strix Point Mobile. The Radeon RX 7800M uses RDNA 3.0 on a 5 nm process with the Navi 32 chip, codenamed Wheat Nas, and belongs to the Navi Mobile (RX 7000M) generation.

Transistor density differs substantially. The RX 7800M packs 28,100 million transistors into a 346 mm² die, yielding a density of 81.2 million transistors per square millimeter. The 820M's transistor count and die size are not recorded, so direct density comparison is not possible from the data.

The RX 7800M has a much larger execution pipeline. Its 3840 shading units, 240 TMUs, and 96 ROPs dwarf the 820M's 128 shading units, 8 TMUs, and 4 ROPs. Ray tracing hardware also differs: 60 RT cores on the RX 7800M versus 2 RT cores on the 820M. Neither GPU has tensor cores recorded in the database.

Memory architecture represents a fundamental split. The 820M relies entirely on system shared memory with bandwidth described as system dependent. The RX 7800M uses dedicated 12 GB GDDR6 on a 192-bit interface with a fixed 432.0 GB/s bandwidth and a 2250 MHz memory clock. This dedicated memory configuration removes contention with the CPU and provides predictable performance.

The bus interface also differs. The 820M connects via PCIe 4.0 x8, while the RX 7800M uses PCIe 4.0 x16, giving the latter twice the lanes for data transfer between GPU and system. Both are classified as IGP slot width with no power connectors and portable-device-dependent display outputs.

Specification Differences

The recorded specifications show clear separation between the two GPUs. The Radeon 820M operates at 400 MHz base and 2800 MHz boost with no game clock listed. The RX 7800M runs at 1295 MHz base, 2145 MHz game clock, and 2335 MHz boost. The 820M's boost clock is higher, but its base clock is substantially lower.

Memory specifications differ completely. The 820M uses system shared memory with system-dependent bandwidth, while the RX 7800M has 12 GB GDDR6, 192-bit bus width, 432.0 GB/s bandwidth, and 2250 MHz memory clock at 18 Gbps effective speed.

Compute resources show a 30x difference in shading units: 128 versus 3840. TMUs differ by 30x as well, with 8 versus 240. ROPs show a 24x gap at 4 versus 96. Ray tracing cores are 2 versus 60, a 30x difference.

Pixel and texture rates reflect these resource gaps. The 820M achieves 11.20 GPixel/s and 22.40 GTexel/s. The RX 7800M delivers 224.2 GPixel/s and 560.4 GTexel/s. FP32 performance is 716.8 GFLOPS versus 35.87 TFLOPS, a 50x difference. Both have FP16 at 1:1 ratio with FP32.

Power consumption shows a major split: 15 W for the 820M versus 180 W for the RX 7800M. Release dates differ, with the RX 7800M released on 2024-09-10 and the 820M on 2025-02-28. The RX 7800M's predecessor is Polaris Mobile, while the 820M's predecessor is Navi II IGP. Neither has a successor or launch MSRP recorded.

Head-to-Head Benchmarks

The database contains benchmark results only for the Radeon RX 7800M. The 820M has no recorded benchmark scores, and the head-to-head benchmark array is empty. This means the RX 7800M holds all measured wins by default.

The RX 7800M's strongest results come from Geekbench tests. Its Vulkan score of 126668 and OpenCL score of 120778 indicate substantial compute capability. These scores reflect the GPU's 3840 shading units and 35.87 TFLOPS FP32 throughput.

In 3DMark Steel Nomad DX12, the RX 7800M scores 2994. This test measures modern DirectX 12 workloads and the score indicates strong rasterization performance. The GPU's 224.2 GPixel/s pixel rate and 560.4 GTexel/s texture rate support this result.

Passmark tests show varied results. The G3D score of 17613 is the flagship metric, while GPU Compute scores 9342. DirectX tests show 176 for DX11, 99 for DX10, 89 for DX12, and 174 for DX9. The G2D score of 892 covers 2D graphics workloads.

The average benchmark score places the RX 7800M at 27883, which corresponds to the 73rd percentile among all GPUs. This percentile ranking puts it ahead of 73% of all recorded GPUs in the database. Its nearest rivals are tightly clustered: the AMD Radeon Pro Vega 20 scores 27839, which is 0.2% behind; the AMD Radeon Pro W5500X scores 27973, 0.3% ahead; the NVIDIA GeForce GTX 980 Ti scores 28020, 0.5% ahead; and the AMD FirePro S7150 scores 28117, 0.8% ahead.

This tight clustering indicates the RX 7800M sits in a competitive performance band. The data shows a 0.8% spread across its four nearest rivals, suggesting the RX 7800M delivers performance comparable to those established GPUs. The 820M's 50th percentile ranking with an average score of 0 places it in a different performance class entirely.

The Verdict

The data indicates two GPUs designed for entirely different purposes. The AMD Radeon 820M targets low-power integrated graphics with a 15 W TDP, system shared memory, and a compact 4 nm design. Its 50th percentile ranking and 128 shading units place it in the entry-level integrated segment. The 2 RT cores and 716.8 GFLOPS FP32 performance serve basic graphics and light compute tasks.

The AMD Radeon RX 7800M delivers dedicated mobile graphics performance. Its 73rd percentile ranking, 27883 average benchmark score, and 12 GB GDDR6 memory position it as a high-performance mobile solution. The 3840 shading units, 60 RT cores, and 35.87 TFLOPS FP32 throughput provide the compute resources for demanding gaming and professional workloads. Its 180 W TDP and PCIe 4.0 x16 interface reflect a design built for maximum throughput rather than efficiency.

The RX 7800M's benchmark results confirm its performance class. Geekbench scores above 120000 in both OpenCL and Vulkan, a 3DMark Steel Nomad score of 2994, and a Passmark G3D score of 17613 all point to a GPU capable of handling intensive graphics workloads. The tight clustering of its nearest rivals, all within 0.8%, validates its position in the performance hierarchy.

Users requiring dedicated graphics memory, high compute throughput, and ray tracing capability should select the RX 7800M. Users needing minimal power draw, integrated simplicity, and a newer manufacturing process should consider the 820M. The RX 7800M wins every recorded benchmark and dominates in every measurable specification except boost clock, power efficiency, and process node. The 820M offers a modern RDNA 3.5 architecture and 4 nm process, but its performance ceiling is far below the RX 7800M's established results.