A40 vs B300: Specs, VRAM & Price
Short answer: choose the B300 when 288 GB of VRAM is the gating requirement. Choose the A40 when 48 GB is enough for the workload and the lower hourly rate points that way.
The A40 has 48 GB of VRAM; the B300 has 288 GB.
You can rent both by the hour, no purchase required. A40 from $0.649/GPU/hr; B300 from $9.89/GPU/hr. The A40 is 93% cheaper at the entry rate.
A40
Good for training and inference on models that don't need FP8 kernels
B300
Good for training and serving frontier-scale LLMs
Last updated: 2026-10-10 22:40:35 UTCRefreshes hourly
Specs side by side
| Spec | A40 | B300 |
|---|---|---|
| VRAM | 48 GB | 288 GB |
| Architecture | Ampere | Blackwell Ultra |
| Compute capability | 8.6 | 10.3 |
| Precisions in hardware | FP32, FP16, BF16, INT4 | FP32, FP16, BF16, FP8, INT4 |
| Regions | 1 | 1 |
On-demand price
| Rate | A40 | B300 |
|---|---|---|
| Lowest per GPU/hr | $0.649/GPU/hr | $9.89/GPU/hr |
Which is better for AI: A40 or B300?
Choose the B300 when 288 GB of VRAM is the gating requirement. Choose the A40 when 48 GB is enough for the workload and the lower hourly rate points that way.
A40 vs B300: common questions
Is the A40 or the B300 better for AI?
Short answer: choose the B300 when 288 GB of VRAM is the gating requirement. Choose the A40 when 48 GB is enough for the workload and the lower hourly rate points that way.
Is the A40 or the B300 cheaper to rent?
On Aquanode's live marketplace the A40 starts at $0.649/GPU/hr (median $0.649/GPU/hr) and the B300 starts at $9.89/GPU/hr (median $9.89/GPU/hr). The A40 is the cheaper of the two at the entry rate, by 93%.
What is the difference between the A40 and the B300?
The A40 has 48 GB of VRAM against the B300's 288 GB; the A40 is an Ampere part and the B300 is Blackwell Ultra (compute capability 8.6 vs 10.3); only the B300 supports FP8 compute. On price, the A40 lists from $0.649/GPU/hr and the B300 from $9.89/GPU/hr.
How widely available are the A40 and the B300?
The A40 is listed in 1 region and the B300 in 1 region right now.
How much does 1,000 GPU-hours cost on the A40 vs the B300?
At the lowest rates listed today, 1,000 GPU-hours costs $649 on the A40 and $9,889 on the B300, a difference of $9,240 for the same runtime. Rates are per GPU per hour and update hourly.
How much VRAM does the A40 have compared to the B300?
The A40 has 48 GB of VRAM; the B300 has 288 GB.
How this comparison is calculated
Every price is normalized to a per-GPU hourly rate using the same pipeline as every other pricing surface on Aquanode, and only the cheapest qualifying offer per provider is shown. A dash means that provider does not currently list that GPU.
Architecture, compute capability and supported precisions come from each vendor's published datasheet for that generation, not from the marketplace feed. This page regenerates at most once per hour.
Memory bandwidth, tensor TFLOPS, NVLink/interconnect and max board power are the same verified-from-datasheet figures shown on each model's own A40 page and B300 page, which link the primary vendor source for that model. A dash here means Aquanode hasn't verified that figure from a primary source yet, never a guess.
Go further
Check what fits in each card's memory with the A40 VRAM calculator and the B300 VRAM calculator, or browse every model by generation in the GPU index.
More A40 comparisons
More B300 comparisons
Related reading: H100 pricing and specs, H100 vs H200, A100 vs H100, H100 and H200: SXM vs NVL vs PCIe, and The best GPUs for AI, ranked.
