AMD Radeon 840M vs NVIDIA H100 CNX Comparison

Head-to-Head Benchmarks

The database contains no direct head-to-head benchmark results for the AMD Radeon 840M and the NVIDIA H100 CNX. Both products have an average benchmark score of 0 and a percentile ranking of 50 among all GPUs in the database. This absence of recorded performance data means no direct comparison of frame rates, compute throughput, or rendering scores can be made from the available measurements. The Radeon 840M and H100 CNX occupy entirely different product categories, and their recorded data reflects that separation.

Where Each One Wins

Without benchmark scores, the wins must be assessed from the architectural and specification data. The AMD Radeon 840M is an integrated graphics processor (IGP) built for mobile platforms, with a 15 W TDP. Its advantage lies in power efficiency and portability. The H100 CNX is a dual-slot server accelerator with a 350 W TDP, designed for data center workloads. The H100 CNX carries 80 GB of HBM2e memory with a 5120-bit bus and 2.04 TB/s bandwidth, while the Radeon 840M uses system-shared memory with bandwidth that is system dependent. In terms of raw compute, the H100 CNX delivers 53.84 TFLOPS of FP32 performance versus the Radeon 840M's 1,484.8 GFLOPS. The H100 CNX also has 456 tensor cores, which the Radeon 840M lacks entirely. The Radeon 840M does include 4 ray tracing cores, while the H100 CNX lists no ray tracing cores. For FP16 workloads, the H100 CNX reaches 215.4 TFLOPS with a 4:1 ratio, whereas the Radeon 840M delivers 1,484.8 GFLOPS at a 1:1 ratio. The H100 CNX's pixel rate is 44.28 GPixel/s, nearly double the Radeon 840M's 23.20 GPixel/s. Texture rate similarly favors the H100 CNX at 841.3 GTexel/s versus 46.40 GTexel/s.

Architecture Differences

The AMD Radeon 840M uses the Krackan Point chip built on TSMC's 4 nm process, with the RDNA 3.5 architecture. It belongs to the Navi III IGP generation for Strix Point Mobile. The NVIDIA H100 CNX uses the GH100 chip on TSMC's 5 nm process, with the Hopper architecture and belongs to the Server Hopper generation. The H100 CNX integrates 80,000 million transistors on an 814 mm² die, achieving a transistor density of 98.3M per mm². The Radeon 840M's transistor count and die size are listed as unknown. Clock behavior differs substantially: the Radeon 840M has a 400 MHz base and 2900 MHz boost, while the H100 CNX runs at 690 MHz base and 1845 MHz boost, with its memory clocked at 1593 MHz or 3.2 Gbps effective. The Radeon 840M has 256 shading units, 16 texture mapping units, 8 ROPs, and 4 ray tracing cores. The H100 CNX has 14,592 shading units, 456 TMUs, 24 ROPs, and 456 tensor cores. The memory subsystem is entirely different: the Radeon 840M relies on system-shared memory with no dedicated VRAM, while the H100 CNX uses 80 GB of HBM2e across a 5120-bit interface. The H100 CNX connects via PCIe 5.0 x16, while the Radeon 840M uses PCIe 4.0 x8. The H100 CNX has no display outputs, while the Radeon 840M's display outputs are portable device dependent. API support also diverges: the Radeon 840M supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4, while the H100 CNX lists no DirectX, OpenGL, or Vulkan support in the database.

FAQ

Q: Which GPU has more shading units?

A: The NVIDIA H100 CNX has 14,592 shading units, while the AMD Radeon 840M has 256 shading units.

Q: What is the memory capacity difference?

A: The H100 CNX has 80 GB of HBM2e memory with a 5120-bit bus and 2.04 TB/s bandwidth. The Radeon 840M uses system-shared memory with a system-dependent bandwidth.

Q: Does the H100 CNX support DirectX?

A: No DirectX support is recorded for the H100 CNX. The Radeon 840M supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4.

Q: Which GPU has a higher boost clock?

A: The AMD Radeon 840M has a boost clock of 2900 MHz, while the NVIDIA H100 CNX has a boost clock of 1845 MHz.

Q: What are the power requirements?

A: The Radeon 840M has a 15 W TDP and is an integrated GPU with no power connectors. The H100 CNX has a 350 W TDP, uses an 8-pin EPS connector, and has a suggested PSU of 750 W.

Q: When were these GPUs released?

A: The AMD Radeon 840M was released on 2025-02-28, and the NVIDIA H100 CNX was released on 2023-03-20.

Specification Differences

| Specification | AMD Radeon 840M | NVIDIA H100 CNX |

|----------------|-----------------|-----------------|

| Architecture | RDNA 3.5 | Hopper |

| Process Node | 4 nm | 5 nm |

| Transistors | Unknown | 80,000 million |

| Die Size | Unknown | 814 mm² |

| Transistor Density | Not listed | 98.3M / mm² |

| Base Clock | 400 MHz | 690 MHz |

| Boost Clock | 2900 MHz | 1845 MHz |

| Memory Size | System Shared | 80 GB |

| Memory Type | System Shared | HBM2e |

| Memory Bus Width | System Shared | 5120 bit |

| Memory Bandwidth | System Dependent | 2.04 TB/s |

| Shading Units | 256 | 14,592 |

| TMUs | 16 | 456 |

| ROPs | 8 | 24 |

| RT Cores | 4 | Not listed |

| Tensor Cores | Not listed | 456 |

| Pixel Rate | 23.20 GPixel/s | 44.28 GPixel/s |

| Texture Rate | 46.40 GTexel/s | 841.3 GTexel/s |

| FP32 Performance | 1,484.8 GFLOPS | 53.84 TFLOPS |

| FP16 Performance | 1,484.8 GFLOPS (1:1) | 215.4 TFLOPS (4:1) |

| TDP | 15 W | 350 W |

| Slot Width | IGP | Dual-slot |

| Power Connectors | None | 8-pin EPS |

| Suggested PSU | Not listed | 750 W |

| Bus Interface | PCIe 4.0 x8 | PCIe 5.0 x16 |

| Display Outputs | Portable Device Dependent | No outputs |

| DirectX Support | 12 Ultimate (12_2) | Not listed |

| OpenGL Support | 4.6 | Not listed |

| Vulkan Support | 1.4 | Not listed |

| Length | Not listed | 267 mm (10.5 inches) |

| Height | Not listed | 111 mm (4.4 inches) |

| Release Date | 2025-02-28 | 2023-03-20 |

| Predecessor | Navi II IGP | Server Ada |

| Successor | Not listed | Server Blackwell |

The Verdict

The recorded data positions these two GPUs at opposite ends of the hardware spectrum. The AMD Radeon 840M is an integrated part of a mobile platform, drawing only 15 W and relying on system memory. Its 4 nm process, 2900 MHz boost clock, and support for DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4 make it suitable for portable devices where display output is expected and power draw is minimal. The NVIDIA H100 CNX is a server accelerator with 80 GB of HBM2e, 456 tensor cores, and 53.84 TFLOPS of FP32 compute. Its 350 W TDP, dual-slot design, 8-pin EPS connector, and lack of display outputs confirm it is built for data center installations, not desktop or mobile use. The H100 CNX's predecessor is Server Ada and its successor is Server Blackwell, indicating a clear server lineage. The Radeon 840M's predecessor is Navi II IGP, showing its integrated graphics heritage. Benchmark results are absent for both, so the verdict rests on the specification sheets. Users seeking a low-power integrated GPU for a portable device would select the Radeon 840M. Users requiring massive memory bandwidth, tensor core acceleration, and high compute throughput for server workloads would select the H100 CNX. The two products do not compete in the same market segment, and the data reflects no overlap in their design goals.