Specifications Compared
| Spec | GB300 | RTX-4090 |
|---|---|---|
| TDP | 1400W | 450W |
| VRAM | 288 GB | 24 GB |
| Memory Type | HBM3e | GDDR6X |
| Architecture | Blackwell Ultra | Ada Lovelace |
| Form Factors | SXM | PCIe |
| Interconnect | NVSwitch, NVLink | PCIe 4.0 |
| FP8 Performance | 4,500 TFLOPS | 660 TFLOPS |
| FP16 Performance | 2,250 TFLOPS | 165 TFLOPS |
| FP32 Performance | 90 TFLOPS | 82.6 TFLOPS |
| FP64 Performance | 45 TFLOPS | 1.3 TFLOPS |
| INT8 Performance | 4,500 TOPS | 660 TOPS |
| Memory Bandwidth | 12,000 GB/s | 1,008 GB/s |
Performance Analysis
FP16 performance dominates training workloads: the GB300 achieves 2250 TFLOPS compared to the RTX 4090's 165 TFLOPS, enabling faster convergence on large models. FP32 rates show parity at 90 TFLOPS for GB300 and 82.6 TFLOPS for RTX 4090, suitable for precision tasks in scientific computing. This delta means GB300 accelerates deep learning training by over 13 times in raw throughput, though real-world scaling depends on NVLink versus PCIe 4.0 interconnects.
Inference benefits from FP8 capabilities: GB300 delivers 4500 TFLOPS against RTX 4090's 660 TFLOPS, supporting higher throughput for serving LLMs. Memory bandwidth of 12000 GB/s on GB300 versus 1008 GB/s on RTX 4090 allows larger batch sizes without bottlenecks; for instance, 288 GB HBM3e VRAM handles models exceeding 24 GB GDDR6X limits, reducing swapping and latency in inference pipelines.
Power efficiency varies with 1400W TDP for GB300 in multi-GPU clusters versus 450W for single RTX 4090 instances. Datacenter setups favor GB300's NVSwitch for aggregation, while RTX 4090 suits edge or prototyping where availability trumps peak specs.
Live Cloud Pricing
Real-time prices from 25+ providers. Updated every 60 seconds.
RTX 4090
| Provider | GPU Model | VRAM | Host Specs | Region | Price | Status | Action | |
|---|---|---|---|---|---|---|---|---|
 TensorDock | NVIDIA GeForce RTX 4090 24GB VRAM | 24GB | 0 vCPU 0GB RAM | Chubbuck, Idaho | $0.39/GPU/hr | Available | ||
 Vast.ai | NVIDIA GeForce RTX 4090 24GB VRAM | 24GB | 64 vCPU 101GB RAM 140GB Storage | Iceland | $0.44/GPU/hr | Available | ||
Vast.ai | NVIDIA GeForce RTX 4090 24GB VRAM | 24GB | 32 vCPU 88GB RAM 106GB Storage | Iceland | $0.47/GPU/hr | Available | ||
TensorDock | NVIDIA GeForce RTX 4090 24GB VRAM | 24GB | 0 vCPU 0GB RAM | Orlando, Florida | $0.48/GPU/hr | Available | ||
Vast.ai | NVIDIA GeForce RTX 4090 24GB VRAM | 24GB | 32 vCPU 101GB RAM 108GB Storage | Iceland | $0.53/GPU/hr | Available |
When to Choose the GB300
The GB300 excels in hyperscale AI training and inference: its 288 GB HBM3e VRAM accommodates models like trillion-parameter LLMs that overwhelm the RTX 4090's 24 GB. With 12000 GB/s bandwidth and 2250 TFLOPS FP16, it processes massive batches efficiently via NVLink.
When to Choose the RTX 4090
The RTX 4090 fits cost-sensitive, immediate deployments: cloud pricing starts at $0.16 per hour with 96 live offers, versus no availability for GB300. Its 450W TDP and PCIe form enable quick setups for fine-tuning or Stable Diffusion on models under 24 GB, with solid 165 TFLOPS FP16 for prototyping.
Use Cases
GB300's 288 GB VRAM and 2250 TFLOPS FP16 handle massive datasets and models infeasible on RTX 4090's 24 GB and 165 TFLOPS.
4500 TFLOPS FP8 and 12000 GB/s bandwidth on GB300 enable high-throughput serving; RTX 4090's 660 TFLOPS FP8 limits scale.
RTX 4090's 24 GB VRAM and $0.16 per hour pricing suffice for models under 20 GB; GB300 overkill without live offers.
RTX 4090's 165 TFLOPS FP16 and immediate availability support image generation efficiently at lower 450W TDP.
GB300's 90 TFLOPS FP32 and NVLink scaling outperform RTX 4090's 82.6 TFLOPS for large simulations.
Frequently Asked Questions
What is the VRAM difference between GB300 and RTX 4090?▾
GB300 provides 288 GB HBM3e VRAM, while RTX 4090 offers 24 GB GDDR6X. This enables GB300 to load much larger models without offloading.
How does memory bandwidth compare?▾
GB300 delivers 12000 GB/s, exceeding RTX 4090's 1008 GB/s by over 11 times. Higher bandwidth supports larger batch sizes in training.
Is GB300 available for cloud rental?▾
No live offers exist for GB300 currently. RTX 4090 has 96 offers from $0.16 per hour averaging $0.48 per hour.
Which has better FP16 performance?▾
GB300 achieves 2250 TFLOPS FP16 versus RTX 4090's 165 TFLOPS. This gap accelerates AI training significantly.
What are the power requirements?▾
GB300 demands 1400W TDP in SXM form, compared to RTX 4090's 450W in PCIe. GB300 suits clustered datacenters.
Can RTX 4090 handle large LLMs?▾
RTX 4090's 24 GB VRAM limits it to models under that size; GB300's 288 GB supports trillion-parameter LLMs directly.
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 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 FP16 throughput and 11.9x the memory bandwidth of the RTX 4090.