A100 PCIe 80GB vs RTX 3090

AmperevsAmpereUpdated 35 days ago

The A100 PCIe 80GB wins for primary machine learning use cases like LLM training and inference. Its 80 GB VRAM, 312 TFLOPS FP16, and 2039 GB/s bandwidth handle production-scale models infeasible on RTX 3090's 24 GB and 35.6 TFLOPS, justifying higher $2.08 average hourly cost.

A100 PCIe 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 PCIe 80GB outperforms the RTX 3090 in FP16 workloads critical for deep learning: 312 TFLOPS versus 35.6 TFLOPS accelerates matrix multiplications in training neural networks. The RTX 3090 matches in FP32 at 35.6 TFLOPS over A100's 19.5 TFLOPS, suiting graphics or simulations less reliant on half-precision. This FP16 delta means A100 trains models 8.8 times faster in tensor core operations.

Memory bandwidth defines practical limits: A100's 2039 GB/s supports batch sizes up to 2.2 times larger than RTX 3090's 936 GB/s, minimizing per-iteration overhead in large datasets. Higher 80 GB VRAM on A100 fits models exceeding 24 GB without model parallelism, reducing complexity in distributed setups. These factors elevate A100 for production-scale AI, while RTX 3090 handles smaller inference efficiently.

TDP differences of 400W versus 350W influence cluster density, but interconnects like NVLink on both enable multi-GPU scaling, with A100 adding PCIe 4.0 and InfiniBand for datacenter fabrics.

Live Cloud Pricing

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

A100 PCIe 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
$1.07/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 PCIe 80GB

The A100 PCIe 80GB excels in enterprise AI pipelines requiring 80 GB VRAM: it loads full large language models without sharding, unlike the 24 GB RTX 3090 limit. Its 2039 GB/s bandwidth sustains massive batch sizes in training, and 312 TFLOPS FP16 speeds convergence on datasets over 1 TB.

Datacenter deployments favor A100's SXM4 and PCIe forms with InfiniBand: these ensure low-latency scaling across 8+ GPUs via NVLink.

When to Choose the RTX 3090

The RTX 3090 fits cost-sensitive prototyping and inference: entry pricing from $0.08 per hour average $0.46 undercuts A100's $0.89 minimum. Its 24 GB VRAM suffices for models under 20 GB, and 35.6 TFLOPS FP32 aids visualization or fine-tuning.

Single-user workstations prefer RTX 3090's PCIe form and 350W TDP: it delivers balanced performance for Stable Diffusion or gaming-adjacent compute without datacenter overhead.

Use Cases

LLM Training
A100 PCIe 80GB

A100's 80 GB HBM2e VRAM and 312 TFLOPS FP16 enable training billion-parameter LLMs with large batches. RTX 3090's 24 GB GDDR6X requires excessive sharding.

LLM Inference
A100 PCIe 80GB

A100 supports high-concurrency inference on 80 GB models at 2039 GB/s bandwidth. RTX 3090 limits throughput on models over 24 GB.

Fine-tuning
Either

RTX 3090's 35.6 TFLOPS FP32 and $0.46 average hourly cost suit small fine-tunes under 20 GB. A100 accelerates larger ones with 312 TFLOPS FP16.

Stable Diffusion
RTX 3090

RTX 3090's 24 GB VRAM and 936 GB/s bandwidth generate images efficiently at $0.08 per hour entry. A100 overkill for consumer diffusion tasks.

Scientific Computing
A100 PCIe 80GB

A100's 2039 GB/s bandwidth and InfiniBand handle simulations with large grids. RTX 3090's 936 GB/s bottlenecks HPC datasets.

Frequently Asked Questions

Is A100 better than RTX 3090 for machine learning?

A100 outperforms with 312 TFLOPS FP16 versus 35.6 TFLOPS and 80 GB VRAM over 24 GB. It suits large-scale training, while RTX 3090 fits prototyping at lower $0.46 average hourly cost.

What is the VRAM difference between A100 PCIe 80GB and RTX 3090?

A100 provides 80 GB HBM2e; RTX 3090 has 24 GB GDDR6X. This allows A100 to load 3.3 times larger models without parallelism.

How do prices compare for cloud rental?

A100 PCIe 80GB starts at $0.89 per hour average $2.08 across 28 offers. RTX 3090 begins at $0.08 per hour average $0.46 across 42 offers.

A100 vs RTX 3090 memory bandwidth?

A100 achieves 2039 GB/s; RTX 3090 reaches 936 GB/s. Higher bandwidth on A100 supports 2.2 times larger batches in training.

Can RTX 3090 replace A100 in AI training?

RTX 3090 cannot for models over 24 GB due to VRAM limit, despite NVLink support. A100's 312 TFLOPS FP16 provides 8.8 times faster tensor operations.

Power consumption of A100 vs RTX 3090?

A100 draws 400W TDP; RTX 3090 uses 350W. Both support PCIe, but A100 adds SXM4 for dense clusters.

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