NVIDIA A100 SXM4 40 GB vs NVIDIA L40S Comparison

The NVIDIA L40S and NVIDIA A100 SXM4 40 GB represent two distinct generations of NVIDIA's server-class accelerators, and the benchmark data clearly separates them. The L40S, built on the Ada Lovelace architecture, dominates in raw compute and graphics-oriented workloads, while the A100 SXM4 40 GB, based on the older Ampere architecture, retains strengths in memory bandwidth and specific compute ratios. This analysis draws exclusively from the provided fact pack to break down the head-to-head results, architectural divergences, and practical use cases for each card.

Head-to-Head Benchmarks

The head-to-head data is unambiguous: the NVIDIA L40S wins both recorded benchmarks outright. In Geekbench OpenCL, the L40S scores 330,727 against the A100 SXM4 40 GB’s 201,096, a decisive 64.5% advantage. The Vulkan test tells a similar story, with the L40S posting 260,799 versus 173,198, a 50.6% lead. These are not marginal gains; the L40S delivers roughly two-thirds more performance in OpenCL and half again as much in Vulkan.

The average benchmark score reinforces this gap. The L40S averages 295,763 across all tests, while the A100 SXM4 40 GB averages just 187,147. That puts the L40S a full 58% ahead on average. The delta is consistent with the individual tests, suggesting the L40S’s advantage is architectural rather than workload-specific. It is not a matter of one benchmark favoring a particular feature; the L40S simply computes faster across the board.

Looking at the percentile rankings, the L40S sits in the 99th percentile of all GPUs, while the A100 SXM4 40 GB sits in the 98th. That one-point difference masks a substantial performance chasm, as the L40S’s nearest rivals include the AMD Instinct MI300X (330,727 vs 317,994, a -7% delta) and the NVIDIA H200 NVL (334,891, -11.7% delta). The A100 SXM4 40 GB, by contrast, trades blows with cards like the NVIDIA RTX 5000 Ada Generation (187,147 vs 184,664, a 1.3% delta) and the NVIDIA Tesla V100S PCIe 32 GB (194,415, -3.7% delta). The L40S is competing in a higher performance tier entirely.

The win count reflects this: the L40S takes 2 wins, the A100 SXM4 40 GB takes 0. There is no benchmark in the fact pack where the A100 comes out ahead. Even the A100’s closest competitor, the A100 SXM4 80 GB, only manages a 1.9% delta against it, whereas the L40S’s closest rival, the RTX 6000 Ada Generation, is 3% behind. The L40S is not just faster than the A100; it is faster than its own immediate peers by a wider margin than the A100 manages against its own.

The Verdict

From the data alone, the choice is straightforward for raw compute: the NVIDIA L40S wins. Its 64.5% lead in OpenCL and 50.6% lead in Vulkan are too large to ignore. If your workload relies on general-purpose compute, shading, or ray tracing, the L40S is the superior card. Its 91.61 TFLOPS FP32 performance dwarfs the A100 SXM4 40 GB’s 19.49 TFLOPS, a 4.7x difference that explains the benchmark disparity.

However, the A100 SXM4 40 GB is not without a niche. Its memory bandwidth of 1.56 TB/s exceeds the L40S’s 864.0 GB/s by a significant margin. For workloads that are bandwidth-bound rather than compute-bound, the A100’s HBM2e memory could prove more effective despite its lower raw throughput. The A100 also offers 77.97 TFLOPS FP16 performance in a 4:1 ratio, compared to the L40S’s 91.61 TFLOPS FP16 at 1:1. If you are running mixed-precision workloads that leverage the A100’s tensor cores, the FP16 gap is narrower than the FP32 gap suggests.

Who should pick the L40S? Anyone running FP32-heavy tasks, graphics pipelines, or Vulkan-based applications. The 48 GB GDDR6 memory is also larger than the A100’s 40 GB HBM2e, so capacity favors the L40S. Who should pick the A100 SXM4 40 GB? Those whose workloads are constrained by memory bandwidth rather than raw FLOPs, particularly if they need the SXM4 form factor with its 400 W TDP and no display outputs. The A100 is end-of-life, as is the L40S, but the A100’s 2020 release date means it has a longer service history in existing infrastructure.

Architecture Differences

The architectural split is stark. The L40S uses the AD102 chip on TSMC’s 5 nm process, while the A100 SXM4 40 GB uses the GA100 chip on TSMC’s 7 nm node. That process shrink allows the L40S to pack 76,300 million transistors into a 609 mm² die, yielding a transistor density of 125.3M per mm². The A100, by contrast, has 54,200 million transistors on a larger 826 mm² die, with a density of just 65.6M per mm². The L40S is nearly twice as dense, which explains its higher clock speeds: 2520 MHz boost versus the A100’s 1410 MHz.

The L40S belongs to the Ada Lovelace generation (Server Ada, Lxx), while the A100 is from the Ampere generation (Server Ampere, Axx). The L40S’s predecessor is Server Ampere, and its successor is Server Hopper; the A100’s predecessor is Tesla Turing, and its successor is Server Ada. This places the L40S one full generation ahead of the A100.

Feature-wise, the L40S includes 142 ray tracing cores, which the A100 lacks entirely (RT cores are null in the fact pack). The L40S also has 568 tensor cores versus the A100’s 432, and 568 TMUs versus 432. The L40S supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4, while the A100 has no listed API support. The L40S has display outputs (1x HDMI 2.1, 3x DisplayPort 1.4a), whereas the A100 has none. This is a fundamental design split: the L40S is a compute-and-graphics hybrid, while the A100 is a pure compute accelerator.

Specification Differences

The memory subsystems diverge sharply. The L40S has 48 GB of GDDR6 on a 384-bit bus, while the A100 has 40 GB of HBM2e on a 5120-bit bus. The A100’s bandwidth of 1.56 TB/s far exceeds the L40S’s 864.0 GB/s, but the L40S offers 8 GB more capacity. Memory clocks also differ: the L40S runs at 2250 MHz (18 Gbps effective), while the A100 runs at 1215 MHz (2.4 Gbps effective).

Compute units favor the L40S. It has 18,176 shading units, 568 TMUs, and 192 ROPs, versus the A100’s 6,912 shading units, 432 TMUs, and 160 ROPs. Pixel rate is 483.8 GPixel/s for the L40S versus 225.6 GPixel/s for the A100; texture rate is 1,431.4 GTexel/s versus 609.1 GTexel/s. FP32 throughput is 91.61 TFLOPS versus 19.49 TFLOPS. FP16 is 91.61 TFLOPS (1:1) for the L40S versus 77.97 TFLOPS (4:1) for the A100.

Power and physical specs also differ. The L40S draws 300 W and uses a single 16-pin connector, with a suggested PSU of 700 W. The A100 draws 400 W, uses no power connectors (SXM module), and suggests an 800 W PSU. The L40S is a dual-slot card measuring 267 mm by 111 mm; the A100 is an SXM module with no listed dimensions. The L40S uses PCIe 4.0 x16, as does the A100, but the L40S has no listed launch MSRP, and neither does the A100.

FAQ

Q: Which GPU has higher FP32 performance?

A: The NVIDIA L40S, with 91.61 TFLOPS, versus the A100 SXM4 40 GB’s 19.49 TFLOPS.

Q: How much faster is the L40S in Geekbench OpenCL?

A: The L40S scores 330,727 against the A100’s 201,096, a 64.5% advantage.

Q: Does the A100 SXM4 40 GB have any advantage in memory?

A: Yes, its HBM2e memory provides 1.56 TB/s bandwidth, compared to the L40S’s 864.0 GB/s from GDDR6.

Q: Which card has more memory capacity?

A: The L40S has 48 GB, while the A100 SXM4 40 GB has 40 GB.

Q: Are both cards still in production?

A: No, both are listed as end-of-life in the fact pack.

Q: Which GPU supports ray tracing?

A: The L40S, with 142 RT cores; the A100 SXM4 40 GB has no RT cores listed.

Where Each One Wins

The L40S wins in every benchmark category recorded, but the margins vary by workload. In OpenCL, its 64.5% lead suggests a massive advantage in general compute tasks. In Vulkan, the 50.6% lead indicates strong graphics and compute-interface performance. The L40S’s 142 RT cores and display outputs make it the clear choice for any workload involving ray-traced rendering, graphics offload, or hybrid compute-visualization tasks. Its 91.61 TFLOPS FP32 and 483.8 GPixel/s pixel rate are simply in a different class from the A100’s 19.49 TFLOPS and 225.6 GPixel/s.

The A100 SXM4 40 GB wins on memory bandwidth, 1.56 TB/s versus 864.0 GB/s. For data-intensive workloads that saturate memory bandwidth—such as large sparse matrix operations or certain inference tasks—the A100 could close the gap. Its FP16 performance of 77.97 TFLOPS is also closer to the L40S’s 91.61 TFLOPS, though the A100 achieves this at a 4:1 ratio, meaning it trades FP32 throughput for FP16. The A100’s 400 W TDP and SXM form factor may also fit existing server infrastructure designed for that module type.

For most users, the L40S is the better buy: it is faster, cooler (300 W vs 400 W), has more memory, supports modern graphics APIs, and includes ray tracing. The A100’s niche is bandwidth-bound compute in legacy SXM-based systems. The data does not support choosing the A100 for raw speed, but for memory throughput, it remains a viable option. Choose the L40S for compute and graphics; choose the A100 only if your workload is explicitly bandwidth-limited and your chassis requires an SXM module.