Specifications Compared
| Spec | GB300 | 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
The FP16 dense performance of 2250 TFLOPS on the GB300 compared with 165.2 TFLOPS on the RTX 4090 indicates substantially higher throughput for training and inference operations that rely on dense tensor computations. The FP16 with sparsity figures of 4500 TFLOPS versus 330.4 TFLOPS follow the same pattern and support accelerated workloads when sparsity patterns apply. Memory bandwidth of 8000 GB per second on the GB300 versus 1008 GB per second on the RTX 4090 allows larger batch sizes during model execution because data movement keeps pace with the higher arithmetic rates. FP32 performance remains comparable at 75 TFLOPS for the GB300 and 82.6 TFLOPS for the RTX 4090 so precision sensitive tasks show less disparity than lower precision paths.
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.
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When to Choose the GB300
The GB300 suits deployments that require 262 to 288 GB HBM3e memory and 8000 GB per second bandwidth for handling models that exceed the 24 GB capacity of the RTX 4090.
When to Choose the RTX 4090
The RTX 4090 fits environments constrained to 450 W TDP and PCIe form factor where 24 GB GDDR6X memory suffices for the target workload. Its 82.6 TFLOPS FP32 rating exceeds the 75 TFLOPS of the GB300 and its 660.6 TOPS INT8 dense rating provides an alternative for integer operations that do not demand the higher memory capacity of the GB300.
Use Cases
The GB300 supplies 2250 TFLOPS FP16 dense performance and 262 to 288 GB memory that accommodate models beyond the 24 GB limit of the RTX 4090.
The GB300 achieves 4500 TFLOPS FP16 with sparsity and 8000 GB per second bandwidth that enable larger batch processing than the 330.4 TFLOPS and 1008 GB per second of the RTX 4090.
The GB300 offers 4500 TFLOPS FP8 dense performance together with high memory capacity that support fine tuning operations exceeding the RTX 4090 capabilities.
The RTX 4090 delivers adequate 330.3 TFLOPS FP8 dense performance at 450 W TDP for diffusion workloads that fit within 24 GB memory.
The RTX 4090 provides 82.6 TFLOPS FP32 while the GB300 supplies 75 TFLOPS FP32 so selection depends on memory requirements versus power limits.
Frequently Asked Questions
What FP16 performance does each GPU provide in dense mode?▾
The GB300 provides 2250 TFLOPS FP16 dense and the RTX 4090 provides 165.2 TFLOPS FP16 dense. The ratio indicates the GB300 handles dense low precision workloads at more than ten times the rate of the RTX 4090.
How does memory bandwidth differ between the two GPUs?▾
The GB300 reaches 8000 GB per second bandwidth and the RTX 4090 reaches 1008 GB per second bandwidth. Higher bandwidth on the GB300 sustains larger batches during training and inference.
What TDP values apply to the GB300 and RTX 4090?▾
The GB300 operates at 1400 W TDP and the RTX 4090 operates at 450 W TDP. Power delivery and cooling requirements scale directly with these figures.
Which GPU supports FP4 operations?▾
The GB300 lists 13500 TFLOPS FP4 dense and 18000 TFLOPS FP4 with sparsity while the RTX 4090 does not publish FP4 specifications. Only the GB300 enables these lower precision formats.
How do the INT8 dense ratings compare?▾
The GB300 provides 187.5 TOPS INT8 dense and the RTX 4090 provides 660.6 TOPS INT8 dense. Integer workloads may favor the RTX 4090 when memory capacity is not the limiting factor.
Which is cheaper to rent, the GB300 or the RTX 4090?▾
Cloud rental prices for both the GB300 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 GB300 have compared to the RTX 4090?▾
The GB300 has 262 to 288 GB of HBM3e memory. The RTX 4090 has 24 GB of GDDR6X memory.
Can I find GB300 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 GB300 and the RTX 4090?▾
The GB300 uses the Blackwell Ultra architecture (2025) while the RTX 4090 uses Ada Lovelace (2022). The GB300 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
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 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 GB300Every 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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