GPU Comparison

The NVIDIA B300 SXM6 AC and NVIDIA L40 are both server-class accelerators, yet they serve fundamentally different segments of the compute market. Benchmark data shows the B300 SXM6 AC is in a class of its own, scoring in the 100th percentile of all GPUs, while the L40 sits at the 99th percentile. The head-to-head comparison is decisive: the B300 SXM6 AC outperforms the L40 by 11.8% in the sole shared benchmark, Geekbench OpenCL, with scores of 369,831 versus 330,926. However, this narrow average delta masks vast architectural and specification gaps that make each card the correct choice for distinctly different workloads.

Head-to-Head Benchmarks

The only directly comparable data point is the Geekbench OpenCL test, where the NVIDIA B300 SXM6 AC records 369,831 points against the NVIDIA L40’s 330,926 points. This represents an 11.8% advantage for the B300 SXM6 AC, a significant margin in compute performance. This result is consistent with the B300 SXM6 AC’s standing as the top performer in the database, holding a perfect 100th percentile rank among all GPUs. The L40, while still elite at the 99th percentile, trails by a measurable amount.

Looking at the B300 SXM6 AC’s nearest rivals, the data reveals its dominant position. It sits 7% ahead of the NVIDIA B200 (345,482), 10.4% ahead of the NVIDIA H200 NVL (334,891), and 16.3% ahead of the AMD Instinct MI300X (317,994). Against the L40S, a sibling of the L40, the B300 SXM6 AC is 25% faster. These deltas show that the B300 SXM6 AC is not merely incrementally faster; it is the undisputed leader in its peer group.

For the NVIDIA L40, the competitive landscape is different. The data positions it slightly behind its immediate successor, the L40S, by 3.9% (295,763). It is also 1.1% slower than the NVIDIA RTX 6000 Ada Generation (287,237). Conversely, the L40 is 13.1% faster than the NVIDIA L20 (251,147) and 10.7% slower than the AMD Instinct MI300X (317,994). While the L40 trails the B300 SXM6 AC in raw OpenCL performance, its average benchmark score of 284,111 is respectable, though it is heavily influenced by its Vulkan score of 237,295, a test that the B300 SXM6 AC does not have data for. The B300 SXM6 AC’s average score of 369,831 is derived solely from its OpenCL result.

The Verdict

The data dictates a clear separation of use cases. Choose the NVIDIA B300 SXM6 AC if the priority is absolute maximum compute throughput and memory capacity. Its 288 GB of HBM3e memory and 8.19 TB/s bandwidth are without peer in this comparison, and its 11.8% OpenCL lead over the L40 confirms it as the top performer for intensive compute tasks. The B300 SXM6 AC is the definitive choice for workloads that can utilize its massive memory footprint and require the highest possible floating-point performance, as evidenced by its 100th percentile ranking and 7% lead over the B200.

Choose the NVIDIA L40 if the workload benefits from a flexible, standard form factor with display outputs. The L40 is a dual-slot card with 4x DisplayPort 1.4a outputs and a 267 mm length, making it suitable for visual computing and workstation-adjacent tasks that the B300 SXM6 AC, an SXM module with no outputs, cannot handle. The L40’s higher boost clock of 2490 MHz and superior pixel rate of 478.1 GPixel/s, compared to the B300 SXM6 AC’s 48.77 GPixel/s, indicate it is more adept at rasterization and graphics-related workloads. The L40 is also the only option with full API support, including DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4, whereas the B300 SXM6 AC lists N/A for these APIs.

Architecture Differences

The two GPUs are built on entirely different design philosophies. The NVIDIA B300 SXM6 AC uses the GB110 chip based on the Blackwell Ultra architecture, fabricated on a 5 nm process at TSMC. This chip is massive, containing 208,000 million transistors on a 1628 mm² die, yielding a transistor density of 127.8 million per mm². The NVIDIA L40, in contrast, uses the AD102 chip based on the older Ada Lovelace architecture, also on a 5 nm process. Its die is significantly smaller at 609 mm² and contains 76,300 million transistors, resulting in a lower density of 125.3 million per mm².

The memory subsystems are fundamentally different. The B300 SXM6 AC utilizes 288 GB of HBM3e on an 8192-bit bus, delivering 8.19 TB/s of bandwidth. The L40 uses 48 GB of GDDR6 on a 384-bit bus, providing 864.0 GB/s. This 9.5x difference in bandwidth and 6x difference in capacity is a defining architectural feature. The B300 SXM6 AC’s design prioritizes data throughput for large models, while the L40’s GDDR6 setup is more conventional for graphics.

Compute resource allocation diverges sharply. The B300 SXM6 AC has 18,944 shading units, 592 TMUs, but only 24 ROPs. It features 592 tensor cores and no dedicated RT cores listed. The L40 has 18,176 shading units, 568 TMUs, and 192 ROPs. It includes 142 RT cores and 568 tensor cores. The L40’s much higher ROP count (192 vs 24) and presence of RT cores highlight its graphics capability, while the B300 SXM6 AC’s configuration emphasizes tensor operations and raw compute with a minimal raster pipeline.

Clock speeds and power characteristics also tell the story. The B300 SXM6 AC runs at a base clock of 1665 MHz and boosts to 2032 MHz, with a thermal design power (TDP) of 1100 W and a suggested power supply of 1500 W. The L40 operates at a much lower base clock of 735 MHz but boosts higher to 2490 MHz, with a TDP of only 300 W and a suggested PSU of 700 W. The B300 SXM6 AC is a high-power, high-throughput accelerator, while the L40 is more power-efficient and runs cooler per unit of work.

FAQ

Q: Which GPU has a higher Geekbench OpenCL score?

A: The NVIDIA B300 SXM6 AC scores 369,831, which is 11.8% higher than the NVIDIA L40’s 330,926.

Q: How does the memory capacity compare between the two?

A: The B300 SXM6 AC features 288 GB of HBM3e memory, while the L40 features 48 GB of GDDR6 memory.

Q: Does the NVIDIA L40 support display outputs?

A: Yes, the L40 has 4x DisplayPort 1.4a outputs. The B300 SXM6 AC has no display outputs.

Q: What is the difference in their percentile rankings?

A: The B300 SXM6 AC is in the 100th percentile of all GPUs, while the L40 is in the 99th percentile.

Q: Which card has more RT cores?

A: The NVIDIA L40 has 142 RT cores, while the B300 SXM6 AC does not have any RT cores listed in the data.

Q: What is the TDP of each card?

A: The B300 SXM6 AC has a TDP of 1100 W, and the L40 has a TDP of 300 W.

Where Each One Wins

The NVIDIA B300 SXM6 AC wins in raw compute and memory-bound tasks. Its 11.8% OpenCL lead, combined with 288 GB of memory and 8.19 TB/s bandwidth, makes it dominant for large-scale AI training and inference, massive data analytics, and high-performance computing simulations that require enormous datasets to reside in fast memory. Its 76.99 TFLOPS FP32 and FP16 performance, while not as high as the L40’s 90.52 TFLOPS in raw FP32, is delivered in a context of far superior memory throughput. The B300 SXM6 AC is also the better choice for environments looking to maximize density per server, as it is an SXM module designed for high-bandwidth system integration.

The NVIDIA L40 wins in graphics, visualization, and power-constrained environments. Its 192 ROPs and 478.1 GPixel/s pixel rate are orders of magnitude higher than the B300 SXM6 AC’s 24 ROPs and 48.77 GPixel/s, making it suitable for ray tracing, professional visualization, and rendering tasks where RT cores and display outputs are necessary. Its support for DirectX 12 Ultimate and Vulkan 1.4 expands its software compatibility. The L40’s dual-slot form factor and 300 W TDP allow it to be deployed in standard workstations and servers without the specialized cooling and power infrastructure that the 1100 W B300 SXM6 AC requires. The L40’s higher boost clock of 2490 MHz also contributes to its strength in latency-sensitive, single-threaded graphics workloads.

Specification Differences

The following table highlights the key areas where the two accelerators differ, based solely on the provided data.

| Specification | NVIDIA B300 SXM6 AC | NVIDIA L40 |

| :--- | :--- | :--- |

| Chip | GB110 | AD102 |

| Architecture | Blackwell Ultra | Ada Lovelace |

| Generation | Server Blackwell (Bxx) | Server Ada (Lxx) |

| Transistors | 208,000 million | 76,300 million |

| Die Size | 1628 mm² | 609 mm² |

| Transistor Density | 127.8M / mm² | 125.3M / mm² |

| Base Clock | 1665 MHz | 735 MHz |

| Boost Clock | 2032 MHz | 2490 MHz |

| Memory Size | 288 GB | 48 GB |

| Memory Type | HBM3e | GDDR6 |

| Memory Bus Width | 8192 bit | 384 bit |

| Memory Bandwidth | 8.19 TB/s | 864.0 GB/s |

| Memory Clock | 2000 MHz (8 Gbps effective) | 2250 MHz (18 Gbps effective) |

| Shading Units | 18944 | 18176 |

| TMUs | 592 | 568 |

| ROPs | 24 | 192 |

| RT Cores | N/A | 142 |

| Tensor Cores | 592 | 568 |

| Pixel Rate | 48.77 GPixel/s | 478.1 GPixel/s |

| Texture Rate | 1,202.9 GTexel/s | 1,414.3 GTexel/s |

| FP32 TFLOPS | 76.99 | 90.52 |

| FP16 TFLOPS | 76.99 (1:1) | 90.52 (1:1) |

| TDP | 1100 W | 300 W |

| Slot Width | SXM Module | Dual-slot |

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

| Suggested PSU | 1500 W | 700 W |

| Display Outputs | No outputs | 4x DisplayPort 1.4a |

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

| OpenGL | N/A | 4.6 |

| Vulkan | N/A | 1.4 |

| Dimensions | N/A | 267 mm (10.5 inches) |

| Production Status | Active | End-of-life |

| Release Date | 2025-09-10 | 2022-10-12 |