A100 vs A40

The A100 is generally better for large language model training due to its higher throughput and 40 GB of VRAM, which allows fitting larger models or larger batch sizes in a single pass. For smaller models or fine-tuning tasks where cost matters more, both GPUs can be effective.

On Shadeform, the A40 is available from $1.10/hr. The A100 starts from $1.36/hr. Prices vary by provider, region, and contract length. Reserved commitments can reduce hourly costs significantly compared to on-demand pricing.

The A40 has more VRAM at 48 GB, compared to 40 GB on the A100. Higher VRAM allows you to run larger models without quantization, use longer context windows, and process larger batch sizes — all of which improve throughput and reduce latency for memory-bound workloads.

Based on TFLOPS per dollar, the A100 offers better raw compute value at current Shadeform on-demand rates. However, the best choice depends on your specific workload — if you need the extra VRAM or throughput of the A40, paying the premium may be justified by faster job completion and lower total cost.

The A100 is currently available across 5 cloud providers on Shadeform's network, compared to 2 for the A40. Shadeform lets you deploy either GPU across all available providers from a single platform, so you can always find available capacity without manually checking each cloud.

Mixing different GPU types in a single training cluster is generally not recommended, as it creates performance bottlenecks where faster GPUs wait for slower ones. For best results, use a homogeneous cluster of either A100 or A40. Shadeform supports on-demand clusters of up to 64 GPUs of the same type with no commitment required.