Specifications Compared
| Spec | GB300 | 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
Dense FP16 throughput reaches 2250 TFLOPS on the GB300 compared with 209.5 TFLOPS on the RTX 5090. This ratio indicates the GB300 can sustain larger model states during training without frequent host offloads. With sparsity the GB300 reaches 4500 TFLOPS in FP16 while the RTX 5090 reaches 419 TFLOPS. Memory bandwidth of 8000 GB/s on the GB300 versus 1792 GB/s on the RTX 5090 allows the GB300 to support batch sizes several times larger before activation memory saturates. FP32 figures show the RTX 5090 at 104.8 TFLOPS against 75 TFLOPS on the GB300 so workloads that remain in single precision may favor the RTX 5090.
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.
GB300
GB300 is not offered on-demand by any provider we track right now. See the GB300 rental page for last-seen listed prices and a price alert.
RTX 5090
| Provider | Region | GPUs | Per GPU / hr | Instance / hr | Deploy |
|---|---|---|---|---|---|
| Vast.ai | Alberta, CA | 1 | $0.93 | — | Deploy |
| LeaderGPU | The Netherlands | 1 | $2.29 | — | Deploy |
2 providers in stock, 5 offers (cheapest per provider shown). All RTX 5090 offers, price history and alerts
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When to Choose the GB300
The GB300 suits multi node training clusters that require 262-288 GB HBM3e capacity per accelerator. Its 8000 GB/s bandwidth and NVLink interconnect enable scaling across many devices for models that exceed single card limits. Dense FP8 performance at 4500 TFLOPS further accelerates low precision inference pipelines that fit within the higher TDP envelope of 1400W.
When to Choose the RTX 5090
The RTX 5090 fits single user inference or fine tuning sessions where 32 GB GDDR7 and a 575W TDP suffice. Its 104.8 TFLOPS FP32 rating supports scientific workloads that stay in full precision without the overhead of a 1400W power draw. PCIe 5.0 connectivity simplifies integration into existing workstation motherboards.
Use Cases
The GB300 supplies 262-288 GB HBM3e and 2250 TFLOPS dense FP16 that accommodate models too large for 32 GB cards.
Its 4500 TFLOPS dense FP8 and 8000 GB/s bandwidth sustain higher throughput for large batch inference than the RTX 5090 can achieve.
Both cards handle fine-tuning workloads though the GB300 supports larger models while the RTX 5090 fits smaller parameter counts at lower power.
The RTX 5090 provides sufficient 32 GB GDDR7 and 419 TFLOPS dense FP8 for typical image generation tasks without excess power draw.
Its 104.8 TFLOPS FP32 rating exceeds the GB300 figure of 75 TFLOPS for workloads that remain in single precision.
Frequently Asked Questions
What is the memory difference between GB300 and RTX 5090?▾
The GB300 contains 262-288 GB HBM3e while the RTX 5090 contains 32 GB GDDR7. This gap determines the maximum model size each card can hold without partitioning.
How does FP16 performance compare on these GPUs?▾
Dense FP16 reaches 2250 TFLOPS on the GB300 and 209.5 TFLOPS on the RTX 5090. Sparse FP16 reaches 4500 TFLOPS on the GB300 and 419 TFLOPS on the RTX 5090.
Which GPU has higher FP32 throughput?▾
The RTX 5090 lists 104.8 TFLOPS FP32 while the GB300 lists 75 TFLOPS FP32. Workloads that stay in single precision therefore favor the RTX 5090.
What TDP values do the GB300 and RTX 5090 carry?▾
The GB300 carries a 1400W TDP and the RTX 5090 carries a 575W TDP. Power delivery and cooling requirements scale directly with these figures.
Can the GB300 and RTX 5090 share the same interconnect?▾
The GB300 supports NVLink while the RTX 5090 uses PCIe 5.0. Direct NVLink scaling is therefore limited to GB300 systems.
Which card offers more INT8 throughput?▾
The RTX 5090 lists 838 TOPS dense INT8 while the GB300 lists 187.5 TOPS dense INT8. Sparse INT8 reaches 1676 TOPS on the RTX 5090 and 375 TOPS on the GB300.
Which is cheaper to rent, the GB300 or the RTX 5090?▾
Cloud rental prices for both the GB300 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 GB300 have compared to the RTX 5090?▾
The GB300 has 262 to 288 GB of HBM3e memory. The RTX 5090 has 32 GB of GDDR7 memory.
Can I find GB300 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 GB300 and the RTX 5090?▾
The GB300 uses the Blackwell Ultra architecture (2025) while the RTX 5090 uses Blackwell (2025). The GB300 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.
Rent these GPUs
Each GPU page lists every current on-demand offer by provider, per GPU-hour, updated every minute.
Related comparisons
How this page is made
- Specifications come from the NVIDIA, AMD and Intel datasheets for the GB300 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 GB300Every 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.
- All GPUsEvery GPU we track, with current lows and provider counts.