Specifications Compared
| Spec | B300 | RTX 5090 |
|---|---|---|
| TDP | 1400W | 575W |
| VRAM | 262-288 GB | 32 GB |
| CUDA Cores | Not published | 21,760 |
| FP4 (dense) | 13,500 TFLOPS | 1,676 TFLOPS |
| FP8 (dense) | 4,500 TFLOPS | 419 TFLOPS |
| Memory Type | HBM3e | GDDR7 |
| Architecture | Blackwell Ultra | Blackwell |
| FP16 (dense) | 2,250 TFLOPS | 209.5 TFLOPS |
| Form Factors | SXM6 | PCIe |
| INT8 (dense) | 187.5 TOPS | 838 TOPS |
| Interconnect | NVLink, PCIe 6.0, InfiniBand | PCIe 5.0 |
| Tensor Cores | Not published | 680 |
| FP32 Performance | 75 TFLOPS | 104.8 TFLOPS |
| FP64 Performance | 1.25 TFLOPS | 1.6 TFLOPS |
| Memory Bandwidth | 8,000 GB/s | 1,792 GB/s |
| FP4 (with sparsity) | 18,000 TFLOPS | 3,352 TFLOPS |
| FP8 (with sparsity) | 9,000 TFLOPS | 838 TFLOPS |
| FP16 (with sparsity) | 4,500 TFLOPS | 419 TFLOPS |
| INT8 (with sparsity) | 375 TOPS | 1,676 TOPS |
Performance Analysis
The FP16 dense performance of the B300 at 2250 TFLOPS exceeds the FP16 dense performance of the RTX 5090 at 209.5 TFLOPS by a ratio of 10.7 to 1. This ratio indicates substantially higher throughput for training and inference workloads that rely on dense FP16 arithmetic. The FP16 performance with sparsity of the B300 at 4500 TFLOPS likewise exceeds the FP16 performance with sparsity of the RTX 5090 at 419 TFLOPS by a ratio of 10.7 to 1. Memory bandwidth of 8000 GB/s on the B300 compared with 1792 GB/s on the RTX 5090 permits larger batch sizes during memory bound operations. The FP32 performance of the RTX 5090 at 104.8 TFLOPS exceeds the FP32 performance of the B300 at 75 TFLOPS.
Current On-Demand Offers
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When to Choose the B300
The B300 constitutes the better choice for deployments that require VRAM capacity between 262 and 288 GB along with 8000 GB/s bandwidth. Its FP8 dense performance of 4500 TFLOPS and support for NVLink interconnect further suit large scale multi GPU configurations that exceed the capabilities of a single RTX 5090.
When to Choose the RTX 5090
The RTX 5090 constitutes the better choice for installations limited to a TDP of 575W and a PCIe form factor. Its FP32 performance of 104.8 TFLOPS supplies an advantage in workloads that depend on single precision floating point calculations.
Use Cases
The B300 supplies FP16 dense performance of 2250 TFLOPS and VRAM capacity up to 288 GB which accommodates training runs that exceed the 32 GB limit of the RTX 5090.
The B300 supplies FP8 dense performance of 4500 TFLOPS together with 8000 GB/s bandwidth which supports higher throughput inference compared with the RTX 5090 FP8 dense performance of 419 TFLOPS.
The B300 supplies FP16 dense performance of 2250 TFLOPS and memory bandwidth of 8000 GB/s which enable fine tuning of models that require capacity beyond 32 GB.
The RTX 5090 supplies FP32 performance of 104.8 TFLOPS at a TDP of 575W which aligns with desktop generation workloads that do not require the 1400W TDP of the B300.
The B300 supplies higher FP16 dense performance of 2250 TFLOPS while the RTX 5090 supplies higher FP32 performance of 104.8 TFLOPS so selection depends on the required precision.
Frequently Asked Questions
What is the memory bandwidth difference between the B300 and the RTX 5090?▾
The B300 provides 8000 GB/s bandwidth while the RTX 5090 provides 1792 GB/s bandwidth.
How does FP16 dense performance compare between the two GPUs?▾
The B300 lists FP16 dense performance of 2250 TFLOPS while the RTX 5090 lists FP16 dense performance of 209.5 TFLOPS.
What TDP values are specified for each GPU?▾
The B300 lists a TDP of 1400W while the RTX 5090 lists a TDP of 575W.
Which interconnect options does each GPU support?▾
The B300 supports NVLink together with PCIe 6.0 and InfiniBand while the RTX 5090 supports PCIe 5.0.
How does FP32 performance differ between the B300 and the RTX 5090?▾
The B300 lists FP32 performance of 75 TFLOPS while the RTX 5090 lists FP32 performance of 104.8 TFLOPS.
Which is cheaper to rent, the B300 or the RTX 5090?▾
Cloud rental prices for both the B300 and RTX 5090 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 5090?▾
The B300 has 262 to 288 GB of HBM3e memory. The RTX 5090 has 32 GB of GDDR7 memory.
Can I find B300 and RTX 5090 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 5090?▾
The B300 uses the Blackwell Ultra architecture (2025) while the RTX 5090 uses Blackwell (2025). The B300 delivers 10.7x the dense FP16 throughput (2,250 vs 209.5 TFLOPS, both without sparsity) and 4.5x the memory bandwidth of the RTX 5090.
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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 5090. 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 5090Every current offer by provider, daily price history and a price alert.
- GPU price indexHow on-demand prices for the major GPUs have moved, updated daily.
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