A100 SXM4 80GB vs RTX 3090

AmperevsAmpereUpdated 35 days ago

The A100 SXM4 80GB emerges as the winner for primary AI/ML use cases like training and inference. Its 80 GB VRAM and 312 TFLOPS FP16 outperform RTX 3090's 24 GB and 35.6 TFLOPS, enabling larger models and batches despite 3x higher $1.33/hr cost.

A100 SXM4 80GB from $0.73/hrRTX 3090 from $0.20/hr

Specifications Compared

SpecA100RTX-3090
TDP400W350W
VRAM40-80 GB24 GB
CUDA Cores6,91210,496
Memory TypeHBM2eGDDR6X
ArchitectureAmpereAmpere
Form FactorsSXM4, PCIePCIe
InterconnectNVLink, PCIe 4.0, InfiniBandNVLink
Tensor Cores432328
FP16 Performance312 TFLOPS35.6 TFLOPS
FP32 Performance19.5 TFLOPS35.6 TFLOPS
FP64 Performance9.7 TFLOPS
INT8 Performance624 TOPS
Memory Bandwidth2,039 GB/s936 GB/s

Performance Analysis

The A100's 312 TFLOPS FP16 throughput dwarfs the RTX 3090's 35.6 TFLOPS, accelerating half-precision training and inference in deep learning models by nearly 9x. This delta suits transformer-based architectures where FP16 dominates, enabling faster iterations on large datasets. Conversely, the RTX 3090's balanced 35.6 TFLOPS across FP16 and FP32 excels in mixed-precision tasks requiring single-precision compute, such as certain simulations.

Memory bandwidth defines practical limits: the A100's 2039 GB/s versus 936 GB/s allows larger batch sizes in training, reducing overhead and improving throughput for memory-bound workloads. The 80 GB HBM2e capacity on A100 handles models exceeding 24 GB GDDR6X on RTX 3090, preventing out-of-memory errors in large language models. Higher TDP of 400W on A100 supports sustained performance in enterprise cooling setups.

Form factors influence deployment: SXM4 on A100 optimizes multi-GPU scaling via NVLink and InfiniBand, outperforming PCIe-only RTX 3090 in clusters.

Live Cloud Pricing

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

A100 SXM4 80GB

ProviderGPU ModelVRAMHost SpecsRegionPriceStatusAction
Vast.ai
Vast.ai
NVIDIA A100 SXM4 80GB
80GB VRAM
$0.73/GPU/hr
Available
Vast.ai
Vast.ai
2×NVIDIA A100 SXM4 80GB
80GB VRAM
$0.73/GPU/hr
$1.47/hr total (2×)
Available
LeaderGPU
LeaderGPU
8×NVIDIA A100 PCIe 80GB
80GB VRAM
$0.90/GPU/hr
$7.20/hr total (8×)
Available
Vast.ai
Vast.ai
NVIDIA A100 SXM4 80GB
80GB VRAM
$1.00/GPU/hr
Available
Denvr
Denvr
8×NVIDIA A100 SXM4 80GB
80GB VRAM
$1.15/GPU/hr
$9.20/hr total (8×)

RTX 3090

ProviderGPU ModelVRAMHost SpecsRegionPriceStatusAction
TensorDock
TensorDock
NVIDIA GeForce RTX 3090
24GB VRAM
$0.20/GPU/hr
Available
TensorDock
TensorDock
NVIDIA GeForce RTX 3090
24GB VRAM
$0.21/GPU/hr
Available
Vast.ai
Vast.ai
4×NVIDIA GeForce RTX 3090
24GB VRAM
$0.25/GPU/hr
$1.01/hr total (4×)
Available
Vast.ai
Vast.ai
4×NVIDIA GeForce RTX 3090
24GB VRAM
$0.27/GPU/hr
$1.07/hr total (4×)
Available
LeaderGPU
LeaderGPU
8×NVIDIA GeForce RTX 3090
24GB VRAM
$0.29/GPU/hr
$2.29/hr total (8×)
Available

Compare real-time pricing across 25+ providers

When to Choose the A100 SXM4 80GB

Choose the A100 SXM4 80GB for enterprise-scale AI training and inference requiring 80 GB VRAM, such as billion-parameter LLMs. Its 2039 GB/s bandwidth sustains large batch sizes, and 312 TFLOPS FP16 delivers rapid half-precision compute. InfiniBand and NVLink enable efficient multi-node scaling unavailable on consumer setups.

Cloud users prioritize A100 at $1.33/hr average when model size or speed justifies the premium over RTX 3090.

When to Choose the RTX 3090

The RTX 3090 suits cost-sensitive prosumer workflows with 24 GB VRAM sufficient for fine-tuning mid-sized models or Stable Diffusion. At $0.46/hr average, it undercuts A100's $1.33/hr by over 65%, ideal for experimentation or gaming-plus-ML hybrids. Balanced 35.6 TFLOPS FP32/FP16 handles diverse tasks without datacenter infrastructure.

Use Cases

LLM Training
A100 SXM4 80GB

A100's 80 GB HBM2e VRAM accommodates massive LLMs beyond RTX 3090's 24 GB limit. 2039 GB/s bandwidth supports large-batch training efficiently.

LLM Inference
A100 SXM4 80GB

312 TFLOPS FP16 on A100 accelerates high-throughput inference. 80 GB capacity handles full model loading without quantization.

Fine-tuning
Either

RTX 3090's 24 GB suffices for most fine-tuning with 35.6 TFLOPS FP16 at $0.46/hr. A100 excels for parameter-heavy adapters needing 80 GB.

Stable Diffusion
RTX 3090

RTX 3090's 24 GB GDDR6X meets image generation needs at $0.08/hr low. Balanced FP32/FP16 suits creative workflows without A100 overhead.

Scientific Computing
A100 SXM4 80GB

A100's 2039 GB/s bandwidth and 312 TFLOPS FP16 optimize simulations. NVLink scales HPC clusters better than RTX 3090.

Frequently Asked Questions

Which has more VRAM, A100 SXM4 80GB or RTX 3090?

The A100 provides 80 GB HBM2e VRAM. RTX 3090 offers 24 GB GDDR6X. This gap favors A100 for large-model workloads.

What is the FP16 performance difference between A100 and RTX 3090?

A100 delivers 312 TFLOPS FP16. RTX 3090 achieves 35.6 TFLOPS. A100 suits accelerated AI training by nearly 9x.

How do cloud prices compare for A100 vs RTX 3090?

A100 starts at $0.45/hr, averages $1.33/hr across 29 offers. RTX 3090 from $0.08/hr, averages $0.46/hr across 41 offers. RTX 3090 offers better value for lighter tasks.

Which GPU has higher memory bandwidth?

A100 bandwidth reaches 2039 GB/s with HBM2e. RTX 3090 provides 936 GB/s GDDR6X. Higher A100 rate enables larger batches.

Is RTX 3090 a good A100 alternative for ML?

RTX 3090 works for models under 24 GB at $0.46/hr average. A100's 80 GB and 312 TFLOPS FP16 outperform for scale. Choose based on model size.

What are the TDPs of A100 and RTX 3090?

A100 TDP is 400W. RTX 3090 TDP is 350W. A100 demands robust cooling for sustained loads.

Which is cheaper to rent, the A100 or the RTX 3090?

Cloud rental prices for both the A100 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 A100 have compared to the RTX 3090?

The A100 has 40 to 80 GB of HBM2e memory. The RTX 3090 has 24 GB of GDDR6X memory.

Can I find A100 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 A100 and the RTX 3090?

The A100 uses the Ampere architecture (2020) while the RTX 3090 uses Ampere (2020). The A100 delivers 8.8x the FP16 throughput and 2.2x the memory bandwidth of the RTX 3090.

A100 SXM4 80GB vs RTX 3090: 8.8x FP16 Gap, 80GB vs 24GB | GPUPerHour