Specifications Compared
| Spec | GB300 | RTX 3090 |
|---|---|---|
| TDP | 1400W | 350W |
| VRAM | 262-288 GB | 24 GB |
| CUDA Cores | Not published | 10,496 |
| FP4 (dense) | 13,500 TFLOPS | Not published |
| FP8 (dense) | 4,500 TFLOPS | Not published |
| Memory Type | HBM3e | GDDR6X |
| Architecture | Blackwell Ultra | Ampere |
| FP16 (dense) | 2,250 TFLOPS | 71 TFLOPS |
| Form Factors | SXM6 | PCIe |
| INT8 (dense) | 187.5 TOPS | 284 TOPS |
| Interconnect | NVLink, PCIe 6.0, InfiniBand | NVLink, PCIe 4.0 |
| Tensor Cores | Not published | 328 |
| FP32 Performance | 75 TFLOPS | 35.6 TFLOPS |
| FP64 Performance | 1.25 TFLOPS | Not published |
| Memory Bandwidth | 8,000 GB/s | 936 GB/s |
| FP4 (with sparsity) | 18,000 TFLOPS | Not published |
| FP8 (with sparsity) | 9,000 TFLOPS | Not published |
| FP16 (with sparsity) | 4,500 TFLOPS | 142 TFLOPS |
| INT8 (with sparsity) | 375 TOPS | 568 TOPS |
Performance Analysis
The 2250 TFLOPS FP16 dense rating on the GB300 exceeds the 71 TFLOPS FP16 dense rating on the RTX 3090 by a factor of 31.7 while the 4500 TFLOPS FP16 with sparsity rating exceeds the 142 TFLOPS FP16 with sparsity rating by the same factor. This delta allows the GB300 to complete matrix operations in training and inference at substantially higher throughput when operating in dense mode or sparsity mode. The 75 TFLOPS FP32 rating on the GB300 likewise exceeds the 35.6 TFLOPS FP32 rating on the RTX 3090. Memory bandwidth of 8000 GB per second on the GB300 supports larger batch sizes than the 936 GB per second bandwidth on the RTX 3090 because data movement keeps pace with the higher arithmetic throughput. The 187.5 TOPS INT8 dense rating on the GB300 remains below the 284 TOPS INT8 dense rating on the RTX 3090 yet the GB300 INT8 with sparsity rating of 375 TOPS still exceeds the RTX 3090 INT8 with sparsity rating of 568 TOPS only when sparsity is applied.
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 3090
| Provider | Region | GPUs | Per GPU / hr | Instance / hr | Deploy |
|---|---|---|---|---|---|
| LeaderGPU | The Netherlands | 8 | $0.29 | $2.29 | Deploy |
| RunPod | global | 1 | $0.50 | — | Deploy |
2 providers in stock, 9 offers (cheapest per provider shown). All RTX 3090 offers, price history and alerts
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When to Choose the GB300
The GB300 suits training or inference of models that require more than 24 GB VRAM because its 262 to 288 GB HBM3e capacity accommodates larger layers without partitioning.
When to Choose the RTX 3090
The RTX 3090 suits inference or fine tuning tasks that fit within 24 GB VRAM and operate at INT8 dense throughput where its 284 TOPS rating exceeds the 187.5 TOPS rating of the GB300. Lower 350 watt TDP and PCIe form factor also align with deployments that cannot accommodate 1400 watt SXM6 modules.
Use Cases
The GB300 supplies 2250 TFLOPS FP16 dense and 262 to 288 GB VRAM that accommodate models beyond the 24 GB limit of the RTX 3090.
FP16 dense throughput of 2250 TFLOPS on the GB300 supports higher token rates than the 71 TFLOPS FP16 dense rating on the RTX 3090.
Both GPUs handle fine tuning when model size fits in 24 GB yet the GB300 extends capacity to 262 to 288 GB for larger adapters.
The RTX 3090 INT8 dense rating of 284 TOPS exceeds the 187.5 TOPS rating of the GB300 for diffusion workloads that remain within 24 GB.
FP32 performance of 75 TFLOPS on the GB300 exceeds the 35.6 TFLOPS rating on the RTX 3090 while bandwidth of 8000 GB per second sustains larger grids.
Frequently Asked Questions
What is the FP16 dense performance difference between the two GPUs?▾
The GB300 reaches 2250 TFLOPS FP16 dense whereas the RTX 3090 reaches 71 TFLOPS FP16 dense.
Which GPU has higher memory bandwidth?▾
The GB300 reaches 8000 GB per second while the RTX 3090 reaches 936 GB per second.
How do the TDP values compare?▾
The GB300 TDP is 1400 watts and the RTX 3090 TDP is 350 watts.
Does the GB300 support higher precision formats than the RTX 3090?▾
The GB300 lists FP8 dense at 4500 TFLOPS and FP4 dense at 13500 TFLOPS while the RTX 3090 does not publish FP8 figures.
Which is cheaper to rent, the GB300 or the RTX 3090?▾
Cloud rental prices for both the GB300 and RTX 3090 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 3090?▾
The GB300 has 262 to 288 GB of HBM3e memory. The RTX 3090 has 24 GB of GDDR6X memory.
Can I find GB300 and RTX 3090 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 3090?▾
The GB300 uses the Blackwell Ultra architecture (2025) while the RTX 3090 uses Ampere (2020). The GB300 delivers 31.7x the dense FP16 throughput (2,250 vs 71 TFLOPS, both without sparsity) and 8.5x the memory bandwidth of the RTX 3090.
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 3090. 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 3090Every 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.