Specifications Compared
| Spec | B300 | RTX 4090 |
|---|---|---|
| TDP | 1400W | 450W |
| VRAM | 262-288 GB | 24 GB |
| CUDA Cores | Not published | 16,384 |
| FP4 (dense) | 13,500 TFLOPS | Not published |
| FP8 (dense) | 4,500 TFLOPS | 330.3 TFLOPS |
| Memory Type | HBM3e | GDDR6X |
| Architecture | Blackwell Ultra | Ada Lovelace |
| FP16 (dense) | 2,250 TFLOPS | 165.2 TFLOPS |
| Form Factors | SXM6 | PCIe |
| INT8 (dense) | 187.5 TOPS | 660.6 TOPS |
| Interconnect | NVLink, PCIe 6.0, InfiniBand | PCIe 4.0 |
| Tensor Cores | Not published | 512 |
| FP32 Performance | 75 TFLOPS | 82.6 TFLOPS |
| FP64 Performance | 1.25 TFLOPS | 1.3 TFLOPS |
| Memory Bandwidth | 8,000 GB/s | 1,008 GB/s |
| FP4 (with sparsity) | 18,000 TFLOPS | Not published |
| FP8 (with sparsity) | 9,000 TFLOPS | 660.6 TFLOPS |
| FP16 (with sparsity) | 4,500 TFLOPS | 330.4 TFLOPS |
| INT8 (with sparsity) | 375 TOPS | 1,321.2 TOPS |
Performance Analysis
Dense FP16 throughput on the B300 reaches 2250 TFLOPS compared with 165.2 TFLOPS on the RTX 4090 producing a ratio of roughly 13.6 times higher arithmetic capacity for the B300. The same pattern holds for dense FP8 where the B300 reaches 4500 TFLOPS against 330.3 TFLOPS on the RTX 4090. FP32 figures reverse the ordering with the RTX 4090 at 82.6 TFLOPS exceeding the B300 at 75 TFLOPS. Memory bandwidth of 8000 GB/s on the B300 versus 1008 GB/s on the RTX 4090 allows the B300 to sustain larger batch sizes during training or inference passes that move substantial activation tensors. Sparse FP16 performance follows the identical ratio with the B300 at 4500 TFLOPS versus 330.4 TFLOPS on the RTX 4090.
Current On-Demand Offers
Cheapest secure on-demand offer per provider that is reported in stock right now, per GPU per hour; multi-GPU instances show the whole-instance price alongside. Deploy opens the DeployGPU console for providers on the platform, otherwise the provider's own site. Stock is rechecked every minute.
B300
1 provider in stock, 1 offer. All B300 offers, price history and alerts
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When to Choose the B300
The B300 suits workloads that require 262 to 288 GB HBM3e memory and 8000 GB/s bandwidth such as training or inference of models whose parameters exceed the 24 GB capacity of the RTX 4090. Its dense FP16 rating of 2250 TFLOPS and dense FP8 rating of 4500 TFLOPS further support high throughput on large tensor operations that fit within the higher power envelope of 1400W.
When to Choose the RTX 4090
The RTX 4090 fits tasks constrained to 450W TDP and 24 GB GDDR6X memory where FP32 throughput of 82.6 TFLOPS exceeds the 75 TFLOPS of the B300. Its dense INT8 rating of 660.6 TOPS also supports inference pipelines that remain within PCIe form factor limits without NVLink interconnect.
Use Cases
The B300 supplies 262 to 288 GB memory and 2250 TFLOPS dense FP16 allowing training runs that exceed the 24 GB limit of the RTX 4090.
Dense FP8 performance of 4500 TFLOPS together with 8000 GB/s bandwidth on the B300 enables larger batch inference than the 330.3 TFLOPS dense FP8 of the RTX 4090.
The B300 262 to 288 GB capacity accommodates full parameter updates on models too large for the RTX 4090 24 GB memory.
The RTX 4090 82.6 TFLOPS FP32 rating and 450W TDP suit diffusion workloads that fit within 24 GB and do not require the higher TDP of the B300.
FP32 throughput of 82.6 TFLOPS on the RTX 4090 exceeds the 75 TFLOPS of the B300 for precision sensitive simulations that remain inside 24 GB memory.
Frequently Asked Questions
What is the memory bandwidth difference between the two GPUs?▾
The B300 lists 8000 GB/s bandwidth whereas the RTX 4090 lists 1008 GB/s bandwidth. The higher figure on the B300 supports larger batch sizes during tensor operations.
Which GPU has higher dense FP16 performance?▾
The B300 reaches 2250 TFLOPS dense FP16 while the RTX 4090 reaches 165.2 TFLOPS dense FP16. The B300 therefore delivers substantially greater throughput on dense half precision workloads.
How do the FP32 ratings compare?▾
The RTX 4090 lists 82.6 TFLOPS FP32 whereas the B300 lists 75 TFLOPS FP32. The RTX 4090 therefore holds a modest advantage in single precision floating point.
What TDP values are specified for each GPU?▾
The B300 carries a 1400W TDP rating while the RTX 4090 carries a 450W TDP rating. Power delivery infrastructure must accommodate the higher figure for the B300.
Which interconnect options appear on each device?▾
The B300 supports NVLink, PCIe 6.0 and InfiniBand while the RTX 4090 supports PCIe 4.0. Multi GPU scaling therefore differs according to these interconnect specifications.
Which is cheaper to rent, the B300 or the RTX 4090?▾
Cloud rental prices for both the B300 and RTX 4090 vary by provider, configuration, and availability. This page shows live pricing from 25+ providers updated every 60 seconds. Scroll to the Live Cloud Pricing section to compare current rates.
How much VRAM does the B300 have compared to the RTX 4090?▾
The B300 has 262 to 288 GB of HBM3e memory. The RTX 4090 has 24 GB of GDDR6X memory.
Can I find B300 and RTX 4090 GPUs available to rent right now?▾
Yes. This page shows real-time availability across 25+ cloud GPU providers. The Live Cloud Pricing section displays only in-stock offers with current pricing.
What is the main difference between the B300 and the RTX 4090?▾
The B300 uses the Blackwell Ultra architecture (2025) while the RTX 4090 uses Ada Lovelace (2022). The B300 delivers 13.6x the dense FP16 throughput (2,250 vs 165.2 TFLOPS, both without sparsity) and 7.9x the memory bandwidth of the RTX 4090.
Rent these GPUs
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Related comparisons
How this page is made
- Specifications come from the NVIDIA, AMD and Intel datasheets for the B300 and the RTX 4090. Dense and sparse throughput are listed separately.
- Prices and availability are live: every offer shown is an in-stock, on-demand listing from a provider we track, rechecked every minute.
- The written comparison (overview, performance notes, when to choose each card, verdict, use cases and FAQ) was drafted with an AI model from the specification table above and passed an automated check that rejects any figure not in that table. It was last generated on . It contains no prices; those are always read live.
- Read how we collect the data, or report an error on this page.
Next steps
- Rent B300Every current offer by provider, daily price history and a price alert.
- Rent RTX 4090Every current offer by provider, daily price history and a price alert.
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