AMD Radeon 840M vs NVIDIA B300 SXM6 AC Comparison

Head-to-Head Benchmarks

The recorded data provides no direct head-to-head benchmark results between the AMD Radeon 840M and the NVIDIA B300 SXM6 AC. The database contains a single benchmark entry for the B300 SXM6 AC: a Geekbench OpenCL score of 369,831. The Radeon 840M has no recorded benchmark scores, and the head-to-head benchmark array is empty. Direct numerical comparison is therefore impossible from the available measurements.

What can be established is the B300 SXM6 AC's position relative to other server accelerators in the database. Its average benchmark score of 369,831 places it in the 100th percentile of all GPUs, meaning it outperforms every other recorded device. Against its nearest rivals, the data shows a 7% lead over the NVIDIA B200, which scores 345,482. The lead extends to 10.4% over the NVIDIA H200 NVL at 334,891, 16.3% over the AMD Instinct MI300X at 317,994, and 25% over the NVIDIA L40S at 295,763. These deltas confirm the B300 SXM6 AC as the top performer in the database, with a margin that grows steadily as rival performance drops.

The Radeon 840M, by contrast, sits at the 50th percentile of all GPUs with an average benchmark score of 0. The absence of any recorded benchmark means the database cannot quantify its performance against the B300 SXM6 AC or any other accelerator. The 840M's percentile rank reflects its position as a mid-tier integrated part, but no score exists to substantiate a direct comparison.

Where Each One Wins

The B300 SXM6 AC wins in every measurable performance category recorded in the database. Its FP32 compute of 76.99 TFLOPS dwarfs the 840M's 1,484.8 GFLOPS, a difference of roughly 52 times in raw shader throughput. FP16 performance follows the same pattern, with both parts delivering a 1:1 ratio: 76.99 TFLOPS for the B300 versus 1,484.8 GFLOPS for the 840M. The texture rate tells a similar story. The B300 reaches 1,202.9 GTexel/s against the 840M's 46.40 GTexel/s, while pixel rates stand at 48.77 GPixel/s versus 23.20 GPixel/s.

Memory capacity and bandwidth favor the B300 overwhelmingly. The B300 carries 288 GB of HBM3e on an 8192-bit bus, delivering 8.19 TB/s of bandwidth. The 840M uses system-shared memory with bandwidth described as system dependent, so no fixed figure exists for comparison. The B300's memory subsystem is a server-class design built for large model residency and high-throughput data movement, while the 840M relies on whatever system memory the host provides.

The 840M does hold advantages in areas unrelated to raw compute. Its power draw of 15 W is dramatically lower than the B300's 1100 W. The 840M is an integrated graphics processor with no power connectors and a slot width of IGP, while the B300 is an SXM module requiring a suggested 1500 W power supply. The 840M also supports display outputs, described as portable device dependent, whereas the B300 has no display outputs at all. For graphics API compatibility, the 840M supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The B300 lists N/A for all three, reflecting its compute-focused role.

Architecture Differences

The two parts come from fundamentally different design lineages. The AMD Radeon 840M uses the Krackan Point chip with RDNA 3.5 architecture, classified under the Navi III IGP generation for Strix Point mobile. It is built on a 4 nm process at TSMC. The NVIDIA B300 SXM6 AC uses the GB110 chip with Blackwell Ultra architecture, belonging to the Server Blackwell (Bxx) generation. It is built on a 5 nm process, also at TSMC.

Transistor and die details diverge sharply. The B300 contains 208,000 million transistors on a 1628 mm² die, with a transistor density of 127.8M per mm². The 840M's transistor count, die size, and density are listed as unknown in the database. The B300's die is a massive server-class package; the 840M is a mobile integrated part with no disclosed silicon measurements.

Compute resources differ by an order of magnitude. The 840M has 256 shading units, 16 texture mapping units, 8 ROPs, and 4 ray tracing cores. The B300 has 18,944 shading units, 592 TMUs, 24 ROPs, and 592 tensor cores. The 840M has no tensor core field recorded. The B300's tensor cores are a defining feature for AI workloads, though the database does not record a ray tracing core count for it.

Clock behavior also differs. The 840M runs at a base clock of 400 MHz and boosts to 2900 MHz. The B300 runs at 1665 MHz base and 2032 MHz boost, with memory clocked at 2000 MHz or 8 Gbps effective. The 840M's memory clock is marked as system shared. The B300 connects via PCIe 6.0 x16, while the 840M uses PCIe 4.0 x8. The B300's predecessor is listed as Server Hopper with a successor of Server Rubin; the 840M's predecessor is Navi II IGP with no successor recorded.

Release timing places the 840M earlier, with a release date of 2025-02-28, while the B300 arrived on 2025-09-10. Both are marked as Active in production status.

FAQ

Q: Which GPU has higher raw FP32 performance?

A: The NVIDIA B300 SXM6 AC delivers 76.99 TFLOPS of FP32 compute, compared to the AMD Radeon 840M's 1,484.8 GFLOPS. The B300 leads by a factor of roughly 52.

Q: How much memory does each GPU have?

A: The B300 SXM6 AC has 288 GB of HBM3e memory on an 8192-bit bus with 8.19 TB/s bandwidth. The 840M uses system-shared memory with system-dependent bandwidth.

Q: What is the power consumption difference?

A: The 840M has a TDP of 15 W and requires no power connectors. The B300 SXM6 AC has a TDP of 1100 W and a suggested power supply of 1500 W.

Q: Does the B300 support DirectX, OpenGL, or Vulkan?

A: The database lists N/A for DirectX, OpenGL, and Vulkan on the B300 SXM6 AC. The 840M supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4.

Q: How does the B300 compare to its nearest rivals?

A: The B300 scores 369,831 in Geekbench OpenCL. That is 7% above the NVIDIA B200 at 345,482, 10.4% above the NVIDIA H200 NVL at 334,891, 16.3% above the AMD Instinct MI300X at 317,994, and 25% above the NVIDIA L40S at 295,763.

Q: What are the interconnect interfaces?

A: The B300 SXM6 AC uses PCIe 6.0 x16. The 840M uses PCIe 4.0 x8.

Specification Differences

| Specification | AMD Radeon 840M | NVIDIA B300 SXM6 AC |

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

| Architecture | RDNA 3.5 | Blackwell Ultra |

| Process Node | 4 nm | 5 nm |

| Transistors | Unknown | 208,000 million |

| Die Size | Unknown | 1628 mm² |

| Transistor Density | Not recorded | 127.8M / mm² |

| Base Clock | 400 MHz | 1665 MHz |

| Boost Clock | 2900 MHz | 2032 MHz |

| Memory Size | System Shared | 288 GB |

| Memory Type | System Shared | HBM3e |

| Memory Bus Width | System Shared | 8192 bit |

| Memory Bandwidth | System Dependent | 8.19 TB/s |

| Shading Units | 256 | 18,944 |

| TMUs | 16 | 592 |

| ROPs | 8 | 24 |

| RT Cores | 4 | Not recorded |

| Tensor Cores | Not recorded | 592 |

| Pixel Rate | 23.20 GPixel/s | 48.77 GPixel/s |

| Texture Rate | 46.40 GTexel/s | 1,202.9 GTexel/s |

| FP32 | 1,484.8 GFLOPS | 76.99 TFLOPS |

| FP16 | 1,484.8 GFLOPS (1:1) | 76.99 TFLOPS (1:1) |

| TDP | 15 W | 1100 W |

| Slot Width | IGP | SXM Module |

| Power Connectors | None | Not recorded |

| Suggested PSU | Not recorded | 1500 W |

| Bus Interface | PCIe 4.0 x8 | PCIe 6.0 x16 |

| Display Outputs | Portable Device Dependent | No outputs |

| DirectX | 12 Ultimate (12_2) | N/A |

| OpenGL | 4.6 | N/A |

| Vulkan | 1.4 | N/A |

| Release Date | 2025-02-28 | 2025-09-10 |

| Predecessor | Navi II IGP | Server Hopper |

| Successor | Not recorded | Server Rubin |

The Verdict

The data separates these two products into entirely different categories. The NVIDIA B300 SXM6 AC is a server accelerator with 288 GB of HBM3e, 8.19 TB/s of memory bandwidth, 76.99 TFLOPS of FP32, and a 100th percentile rank with a Geekbench OpenCL score of 369,831. It leads its nearest recorded rival, the NVIDIA B200, by 7%, and extends that lead to 25% over the NVIDIA L40S. It is designed for maximum compute density, with 18,944 shading units, 592 tensor cores, and a 1100 W power envelope that assumes a 1500 W power supply.

The AMD Radeon 840M is an integrated mobile GPU with 256 shading units, 4 ray tracing cores, 15 W power draw, and system-shared memory. It has no recorded benchmark score, sits at the 50th percentile, and its performance cannot be quantified against the B300 from the available data. What the database does show is that it supports a full graphics API stack, including DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4, and can drive portable device displays.

The choice between them is dictated by workload and platform. The B300 SXM6 AC is for server installations requiring massive memory capacity and the highest recorded compute throughput in the database. The 840M is for portable devices needing an integrated solution with low power consumption and display output. The B300 has no display outputs and no graphics API support, so it cannot serve as a general-purpose graphics card. The 840M lacks the memory, compute resources, and tensor cores for the AI and high-performance compute workloads the B300 targets. The data supports one conclusion: these are complementary products for separate markets, not substitutes.