If vLLM already solved LLM serving, why did SGLang appear?
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This comparison is often framed as a question of which GPU is “better.” In practice, these two GPUs target fundamentally different workload categories.
Deploying an H200 for lightweight 7B inference is usually unnecessary over-provisioning. Using L40S for large-model training or sustained 70B inference introduces hard architectural limits around memory capacity and interconnect bandwidth.
Both GPUs are technically capable AI accelerators. They are simply optimized for different deployment patterns.
The H200 is the stronger choice for:
The L40S is the stronger choice for:
The throughput gap between the two is modest on smaller models and extremely large on larger ones. That distinction is what matters operationally.
In production, these differences become clearer inside an enterprise GPU cloud, where memory capacity, concurrency, and operational consistency matter more than spec-sheet comparisons.
The simplest way to understand the comparison is to separate small-model and large-model behavior.
For smaller models such as 7B–8B:
For larger models such as 70B:
In practical terms:
That larger gap is driven less by raw compute and more by architectural constraints around memory residency, KV cache capacity, and multi-GPU communication.
These are the same constraints that shape high throughput in inference, especially when larger models need predictable latency under concurrent load.
| Spec | H200 SXM | L40S |
| Architecture | Hopper GH100 | Ada Lovelace AD102 |
| Memory | 141 GB HBM3e | 48 GB GDDR6 |
| Memory Bandwidth | 4.8 TB/s | 864 GB/s |
| FP8 Tensor, Sparse | 3,958 TFLOPS | 1,466 TFLOPS |
| BF16 Tensor, Sparse | 1,979 TFLOPS | 733 TFLOPS |
| FP32 | 67 TFLOPS | 91.6 TFLOPS |
| NVLink | 900 GB/s | None |
| PCIe | Gen5 x16 | Gen4 x16 |
| RT Cores | None | 142 |
| MIG | Yes | No |
| TDP | 700 W | 350 W |
Several rows matter more than others.
For LLM workloads, the most important differences are:
The FP32 advantage on L40S is largely irrelevant for modern transformer workloads.
The RT cores on L40S, however, are extremely relevant for rendering, simulation, visualization, and video workloads — areas where H200 is not designed to compete.
H200 is Hopper architecture with expanded HBM capacity and bandwidth.
The key Hopper features include:
These are infrastructure-oriented features optimized for large-scale AI systems.
H200 was designed around modern transformer scaling behavior: larger models, larger batches, larger context windows, and multi-node training.
L40S is based on Ada Lovelace architecture using the AD102 die family.
Operationally, it occupies a different category:
L40S includes:
This makes it attractive for mixed workloads where AI inference and rendering coexist.
The tradeoff is that L40S lacks NVLink entirely.
That absence becomes a major limitation for large-model distributed inference and training.
The clearest difference between these GPUs is memory architecture.
A 70B model in FP16 requires roughly 140 GB just for weights.
H200 can host that model on a single GPU.
L40S cannot.
With only 48 GB of GDDR6 memory, L40S requires:
And because L40S lacks NVLink, all multi-GPU communication runs over PCIe Gen4.
That is a structural bottleneck, not an optimization issue.
The same problem appears with KV cache scaling.
As concurrency and context windows increase:
This is one of the main reasons throughput divergence becomes extreme on large-model inference.
L40S is not positioned as a frontier-scale training GPU.
The reasons are straightforward:
For fine-tuning smaller models, L40S can still be viable.
For large-scale multi-GPU training, it becomes inefficient quickly.
This is reflected across industry benchmarks and deployment patterns. Large-model training workloads overwhelmingly run on H100 or H200-class infrastructure rather than L40S fleets.
H200 exists in the training category. L40S primarily exists in the inference-and-graphics category.
Inference is where L40S can be highly effective — if the workload fits its design envelope.
For smaller LLMs:
For moderate concurrency serving of quantized smaller models, L40S can be a very efficient inference platform.
This is particularly attractive for:
For large-model inference, the picture changes completely.
The issues are:
Quantized multi-GPU deployments on L40S are possible, but operational complexity and performance penalties increase substantially.
For sustained production inference at 70B and above, H200 is the more appropriate architecture.
L40S is substantially cheaper than H200:
For small-model inference, those savings are meaningful.
However, for larger workloads, throughput differences can outweigh hourly price differences.
When comparing infrastructure economics, teams should evaluate:
Not simply hourly GPU pricing.
Infrastructure overhead is one of the biggest practical differences.
For on-prem operators, this distinction materially affects deployment planning and TCO.
L40S supports workloads H200 cannot handle at all.
These include:
If a deployment requires graphics output, rendering pipelines, or simulation environments alongside AI inference, L40S becomes the more appropriate choice regardless of H200’s AI performance advantage.
This is why L40S is frequently positioned as a successor to enterprise visualization GPUs rather than as a direct H200 competitor.
Blackwell-generation systems will expand the gap at the high end of AI infrastructure.
For teams requiring:
Blackwell will eventually become the preferred target.
However, capacity and availability remain limited.
For teams deploying infrastructure in 2026, H200 remains the more broadly accessible high-end AI platform.
L40S currently has no direct Blackwell-era replacement in the AI-plus-graphics category.
The most common mistake in this comparison is treating H200 and L40S as interchangeable AI accelerators.
They are not.
Choose L40S when:
Choose H200 when:
The operationally efficient decision is not choosing the “best” GPU. It is matching the GPU architecture to the actual workload profile.

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