B300 vs RTX 5090

Blackwell UltravsBlackwellUpdated 36 days ago

The B300 emerges as the superior choice for the most common cloud use case of AI model training and inference. Its 2250 TFLOPS FP16 and 288 GB VRAM enable handling massive datasets and models infeasible on the RTX 5090's 419 TFLOPS and 32 GB, justifying the $6.94 per hour cost for production-scale performance.

B300 from $7.39/hrRTX 5090 from $0.57/hr

Specifications Compared

SpecB300RTX-5090
TDP1200W575W
VRAM288 GB32 GB
Memory TypeHBM3eGDDR7
ArchitectureBlackwell UltraBlackwell
Form FactorsSXMPCIe
InterconnectNVSwitch, NVLinkPCIe 5.0
FP8 Performance4,500 TFLOPS838 TFLOPS
FP16 Performance2,250 TFLOPS419 TFLOPS
FP32 Performance90 TFLOPS105 TFLOPS
FP64 Performance45 TFLOPS1.6 TFLOPS
INT8 Performance4,500 TOPS838 TOPS
Memory Bandwidth12,000 GB/s1,792 GB/s

Performance Analysis

The B300 dominates in AI-specific compute with 2250 TFLOPS FP16 performance versus the RTX 5090's 419 TFLOPS, enabling faster model training on large datasets. Its 4500 TFLOPS FP8 rate doubles the RTX 5090's 838 TFLOPS, accelerating inference for quantized models. The FP32 performance shows the RTX 5090 slightly ahead at 105 TFLOPS over the B300's 90 TFLOPS, which suits graphics or simulation tasks less critical for deep learning. In real-world terms, the B300's 288 GB VRAM supports training LLMs with billions of parameters without offloading, while the RTX 5090's 32 GB limits it to smaller models or lower resolutions. Memory bandwidth impacts batch sizes directly: 12000 GB/s on the B300 allows massive batches for efficient training throughput, whereas 1792 GB/s on the RTX 5090 constrains scaling in memory-bound workloads. Interconnects further differentiate them, as the B300's NVSwitch and NVLink enable seamless multi-GPU clusters, unlike the RTX 5090's PCIe 5.0. Power draw reflects this, with the B300 at 1200W TDP demanding robust cooling versus the RTX 5090's efficient 575W.

Live Cloud Pricing

Real-time prices from 25+ providers. Updated every 60 seconds.

B300

ProviderGPU ModelVRAMHost SpecsRegionPriceStatusAction
RunPod
RunPod
NVIDIA B300 SXM6
262GB VRAM
$7.39/GPU/hr
VERDA
VERDA
NVIDIA B300 SXM6
262GB VRAM
$7.50/GPU/hr
Available
VERDA
VERDA
2×NVIDIA B300 SXM6
262GB VRAM
$7.50/GPU/hr
$15.00/hr total (2×)
Available
VERDA
VERDA
8×NVIDIA B300 SXM6
262GB VRAM
$7.50/GPU/hr
$60.00/hr total (8×)
Available
Scaleway
Scaleway
8×NVIDIA B300 SXM6
262GB VRAM
$8.73/GPU/hr
$69.84/hr total (8×)
Available

RTX 5090

ProviderGPU ModelVRAMHost SpecsRegionPriceStatusAction
TensorDock
TensorDock
NVIDIA GeForce RTX 5090
32GB VRAM
$0.57/GPU/hr
Available
Vast.ai
Vast.ai
NVIDIA GeForce RTX 5090
32GB VRAM
$0.81/GPU/hr
Available
Vast.ai
Vast.ai
NVIDIA GeForce RTX 5090
32GB VRAM
$0.87/GPU/hr
Available
Vast.ai
Vast.ai
NVIDIA GeForce RTX 5090
32GB VRAM
$0.91/GPU/hr
Available
Vast.ai
Vast.ai
NVIDIA GeForce RTX 5090
32GB VRAM
$0.91/GPU/hr
Available

Compare real-time pricing across 25+ providers

When to Choose the B300

The B300 excels in large-scale AI deployments requiring extreme memory capacity. Its 288 GB HBM3e VRAM handles models exceeding 100 billion parameters, such as full LLM training runs, where the RTX 5090's 32 GB falls short. High 12000 GB/s bandwidth supports large batch sizes, reducing training time in production environments. Users in enterprise cloud setups benefit from NVLink interconnects for multi-GPU scaling across SXM form factors.

When to Choose the RTX 5090

The RTX 5090 suits cost-conscious prototyping and smaller workloads. At $0.16 per hour from 19 offers, it provides accessible entry for fine-tuning or inference on models fitting within 32 GB GDDR7. Lower 575W TDP fits standard PCIe setups without datacenter infrastructure. Gamers or developers testing Stable Diffusion leverage its 105 TFLOPS FP32 edge over the B300's 90 TFLOPS.

Use Cases

LLM Training
B300

The B300's 288 GB HBM3e VRAM and 2250 TFLOPS FP16 vastly outperform the RTX 5090's 32 GB and 419 TFLOPS, enabling training of large LLMs without memory constraints.

LLM Inference
B300

With 4500 TFLOPS FP8 and 12000 GB/s bandwidth, the B300 serves high-throughput inference on massive models. The RTX 5090's 838 TFLOPS FP8 limits scale for production.

Fine-tuning
Either

Smaller models fit the RTX 5090's 32 GB VRAM for quick iterations at $0.16 per hour. The B300 handles larger fine-tuning with 288 GB but at higher $6.94 per hour cost.

Stable Diffusion
RTX 5090

The RTX 5090's PCIe form factor and 105 TFLOPS FP32 suit image generation workflows. Its low $0.71 per hour average pricing supports creative experimentation.

Scientific Computing
B300

The B300's NVSwitch interconnect and 12000 GB/s bandwidth accelerate simulations across clusters. High FP16 performance aids HPC tasks beyond the RTX 5090's PCIe limits.

Frequently Asked Questions

Which GPU has more VRAM?

The B300 provides 288 GB HBM3e VRAM, dwarfing the RTX 5090's 32 GB GDDR7. This enables the B300 to load massive AI models entirely in memory. The RTX 5090 suits smaller datasets fitting within 32 GB.

What is the price difference in cloud rentals?

The RTX 5090 starts at $0.16 per hour with an average of $0.71 per hour across 19 offers. The B300 begins at $6.94 per hour averaging $7.17 per hour over four offers. Budget users favor the RTX 5090 for testing.

Which offers better FP16 performance?

The B300 delivers 2250 TFLOPS FP16, over five times the RTX 5090's 419 TFLOPS. This accelerates AI training significantly on the B300. Inference workloads also benefit from the gap.

How do memory bandwidths compare?

The B300 achieves 12000 GB/s, nearly seven times the RTX 5090's 1792 GB/s. Higher bandwidth on the B300 supports larger batch sizes in training. The RTX 5090 suffices for lighter loads.

What are the power requirements?

The B300 has a 1200W TDP suited for datacenter cooling in SXM form factors. The RTX 5090 uses 575W TDP for efficient PCIe deployment. Lower power aids consumer setups.

Which is better for multi-GPU setups?

The B300's NVSwitch and NVLink enable high-speed scaling across nodes. The RTX 5090 relies on PCIe 5.0, limiting cluster efficiency. Enterprises choose the B300 for production clusters.

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 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 5.4x the FP16 throughput and 6.7x the memory bandwidth of the RTX 5090.