GB300 SXM6 vs RTX 5090

Blackwell UltravsBlackwellUpdated 35 days ago

The GB300 SXM6 emerges as the clear winner for demanding AI workloads like LLM training and large-scale inference, thanks to its 288 GB VRAM, 12000 GB/s bandwidth, and 2250 TFLOPS FP16. The RTX 5090 cannot match these for enterprise needs, though its availability and low pricing appeal to smaller tasks.

RTX 5090 from $0.57/hr

Specifications Compared

SpecGB300RTX-5090
TDP1400W575W
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 GB300 SXM6 vastly outpaces the RTX 5090 in AI-relevant compute: its 2250 TFLOPS FP16 rate is over five times the RTX 5090's 419 TFLOPS, accelerating deep learning training and inference where half-precision dominates. FP8 performance follows suit at 4500 TFLOPS versus 838 TFLOPS, suiting quantized inference for large language models. FP32 rates are comparable, with GB300 at 90 TFLOPS and RTX 5090 at 105 TFLOPS, so general-purpose computing shows less disparity. Memory capacity defines the real-world gap: 288 GB HBM3e on GB300 supports models exceeding 32 GB GDDR7 on RTX 5090, preventing out-of-memory errors in large-batch training. Bandwidth of 12000 GB/s on GB300 enables batch sizes up to seven times larger than the RTX 5090's 1792 GB/s, reducing training epochs and improving throughput in memory-bound tasks. The GB300's 1400W TDP reflects its scale, contrasting the RTX 5090's efficient 575W for smaller deployments.

Live Cloud Pricing

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

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
$0.87/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 GB300 SXM6

The GB300 SXM6 excels in hyperscale AI training for models requiring over 288 GB VRAM, such as trillion-parameter LLMs, where its 12000 GB/s bandwidth sustains massive batches. NVLink and NVSwitch interconnects make it essential for multi-GPU clusters scaling to thousands of units. Datacenter operators prioritize it for production inference at 4500 TFLOPS FP8, unavailable on consumer cards.

When to Choose the RTX 5090

The RTX 5090 suits cost-sensitive users with its cloud pricing from $0.13 per hour, averaging $0.63 per hour across 30 offers, far below enterprise datacenter costs. It handles fine-tuning or inference for models under 32 GB VRAM efficiently at 419 TFLOPS FP16. PCIe form factor and 575W TDP fit workstations or small clusters without NVLink infrastructure.

Use Cases

LLM Training
GB300 SXM6

GB300's 288 GB HBM3e VRAM and 12000 GB/s bandwidth handle trillion-parameter models with large batches. RTX 5090's 32 GB limits scale.

LLM Inference
GB300 SXM6

4500 TFLOPS FP8 on GB300 accelerates quantized serving for massive models. RTX 5090's 838 TFLOPS FP8 suits only smaller deployments.

Fine-tuning
Either

RTX 5090's 419 TFLOPS FP16 works for models under 32 GB at low cost. GB300 overkill unless batches exceed bandwidth limits.

Stable Diffusion
RTX 5090

RTX 5090's 32 GB GDDR7 and 1792 GB/s suffice for image generation at $0.13 per hour. GB300's scale unnecessary.

Scientific Computing
GB300 SXM6

GB300's 90 TFLOPS FP32 and NVLink enable large simulations. RTX 5090's 105 TFLOPS FP32 fits modest workloads.

Frequently Asked Questions

What is the VRAM difference between GB300 SXM6 and RTX 5090?

GB300 SXM6 offers 288 GB HBM3e, while RTX 5090 provides 32 GB GDDR7. This enables GB300 to load models nine times larger without swapping.

How do FP16 performance rates compare?

GB300 SXM6 achieves 2250 TFLOPS FP16, over five times the RTX 5090's 419 TFLOPS. This boosts AI training speed significantly on GB300.

What are the power requirements?

GB300 SXM6 has a 1400W TDP for datacenter cooling, versus RTX 5090's 575W for standard workstations. Efficiency favors RTX 5090 in small setups.

Is the RTX 5090 available in cloud pricing?

RTX 5090 starts at $0.13 per hour, averaging $0.63 per hour across 30 offers. GB300 SXM6 has no live offers currently.

Which has higher memory bandwidth?

GB300 SXM6 reaches 12000 GB/s, nearly seven times the RTX 5090's 1792 GB/s. Larger batches process faster on GB300.

What interconnects do they use?

GB300 SXM6 employs NVSwitch and NVLink for multi-GPU scaling. RTX 5090 relies on PCIe 5.0 for single-node use.

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