A100 PCIe 40GB vs RTX A4000

AmperevsAmpereUpdated 35 days ago

The A100 PCIe 40GB emerges as the winner for most AI and machine learning use cases: its 312 TFLOPS FP16, 40 GB VRAM, and 2039 GB/s bandwidth deliver unmatched throughput for training and large-model inference, despite 5x higher average pricing at $1.85 per hour. RTX A4000 serves niche, cost-sensitive roles but cannot compete in high-demand scenarios.

A100 PCIe 40GB from $0.73/hrRTX A4000 from $0.08/hr

Specifications Compared

SpecA100RTX-A4000
TDP400W140W
VRAM40-80 GB16 GB
CUDA Cores6,9126,144
Memory TypeHBM2eGDDR6
ArchitectureAmpereAmpere
Form FactorsSXM4, PCIePCIe
InterconnectNVLink, PCIe 4.0, InfiniBand
Tensor Cores432192
FP16 Performance312 TFLOPS19.2 TFLOPS
FP32 Performance19.5 TFLOPS19.2 TFLOPS
FP64 Performance9.7 TFLOPS
INT8 Performance624 TOPS
Memory Bandwidth2,039 GB/s448 GB/s

Performance Analysis

The A100 PCIe 40GB excels in FP16 performance at 312 TFLOPS, enabling faster AI model training where half-precision computations dominate: this represents over 16 times the RTX A4000's 19.2 TFLOPS. FP32 performance remains close, with A100 at 19.5 TFLOPS versus 19.2 TFLOPS on A4000, so single-precision tasks like some scientific simulations show minimal differences. Training large neural networks benefits immensely from the A100's FP16 advantage, reducing epochs from days to hours in scale-out clusters.

Memory specifications define workload feasibility: A100's 40 GB HBM2e and 2039 GB/s bandwidth accommodate massive batch sizes, such as 512+ for transformer models, minimizing data loading bottlenecks. The RTX A4000's 16 GB GDDR6 and 448 GB/s limit it to smaller batches around 32-64, suitable for inference but prone to out-of-memory errors on large models. Power draw underscores efficiency: A100 at 400W suits dense servers, while A4000's 140W fits edge or multi-GPU workstations without high cooling needs.

Inference scenarios highlight bandwidth impact: A100 processes high-resolution inputs at scale, whereas A4000 handles real-time rendering effectively due to its balanced specs.

Live Cloud Pricing

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

A100 PCIe 40GB

ProviderGPU ModelVRAMHost SpecsRegionPriceStatusAction
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
2×NVIDIA A100 SXM4 80GB
80GB VRAM
$1.00/GPU/hr
$2.00/hr total (2×)
Available
Denvr
Denvr
4×NVIDIA A100 PCIe 80GB
80GB VRAM
$1.15/GPU/hr
$4.60/hr total (4×)
Denvr
Denvr
8×NVIDIA A100 SXM4 80GB
80GB VRAM
$1.15/GPU/hr
$9.20/hr total (8×)

RTX A4000

ProviderGPU ModelVRAMHost SpecsRegionPriceStatusAction
TensorDock
TensorDock
NVIDIA RTX A4000
16GB VRAM
$0.08/GPU/hr
Available
Vast.ai
Vast.ai
8×NVIDIA RTX A4000
16GB VRAM
$0.15/GPU/hr
$1.17/hr total (8×)
Available
Hyperstack
Hyperstack
4×NVIDIA RTX A4000
16GB VRAM
$0.15/GPU/hr
$0.60/hr total (4×)
Available
Hyperstack
Hyperstack
2×NVIDIA RTX A4000
16GB VRAM
$0.15/GPU/hr
$0.30/hr total (2×)
Available
Hyperstack
Hyperstack
NVIDIA RTX A4000
16GB VRAM
$0.15/GPU/hr
Available

Compare real-time pricing across 25+ providers

When to Choose the A100 PCIe 40GB

Select the A100 PCIe 40GB for large-scale AI training or inference demanding over 16 GB VRAM, such as LLMs with billions of parameters: its 40 GB HBM2e and 312 TFLOPS FP16 enable batch sizes up to 512 and rapid iterations. Datacenter deployments leverage NVLink for multi-GPU scaling, ideal when cloud costs of $0.60 to $1.85 per hour justify 5x bandwidth superiority over A4000.

When to Choose the RTX A4000

The RTX A4000 fits budget-driven tasks like Stable Diffusion generation or professional visualization: 16 GB GDDR6 suffices for models under 10 GB at $0.08 per hour starting price. Its 140W TDP and 19.2 TFLOPS FP32/FP16 balance make it preferable for single-user workstations or inference on mid-sized models where A100's 400W and higher costs prove excessive.

Use Cases

LLM Training
A100 PCIe 40GB

A100's 40 GB HBM2e VRAM and 312 TFLOPS FP16 support massive models and batch sizes exceeding 256. RTX A4000's 16 GB limits scale.

LLM Inference
A100 PCIe 40GB

High memory bandwidth of 2039 GB/s on A100 enables low-latency serving of large LLMs. A4000's 448 GB/s suits smaller deployments only.

Fine-tuning
A100 PCIe 40GB

A100 handles parameter-efficient fine-tuning on 40 GB datasets with 312 TFLOPS acceleration. A4000 works for tiny models under 16 GB.

Stable Diffusion
RTX A4000

RTX A4000's 16 GB GDDR6 and 19.2 TFLOPS FP16 generate images efficiently at $0.08 per hour. A100 overkill for typical 512x512 resolutions.

Scientific Computing
A100 PCIe 40GB

A100's 19.5 TFLOPS FP32 and NVLink excel in simulations needing high precision and multi-GPU sync. A4000 adequate for lighter HPC only.

Frequently Asked Questions

What is the VRAM difference between A100 PCIe 40GB and RTX A4000?

A100 PCIe 40GB provides 40 GB HBM2e VRAM, while RTX A4000 offers 16 GB GDDR6. This allows A100 to load models over 30 GB without swapping, unlike A4000.

How do FP16 performances compare?

A100 achieves 312 TFLOPS in FP16, over 16 times the RTX A4000's 19.2 TFLOPS. This gap accelerates deep learning training significantly on A100.

What are the cloud pricing ranges?

A100 PCIe 40GB starts at $0.60 per hour averaging $1.85 across 11 offers. RTX A4000 begins at $0.08 per hour averaging $0.37 across 28 offers.

Which has higher memory bandwidth?

A100 leads with 2039 GB/s versus RTX A4000's 448 GB/s. Higher bandwidth on A100 supports larger batches in AI workloads.

What are the TDP ratings?

A100 PCIe 40GB consumes 400W, suited for servers. RTX A4000 uses 140W, ideal for workstations with lower power needs.

Can RTX A4000 replace A100 for AI training?

No, RTX A4000's 16 GB VRAM and 19.2 TFLOPS FP16 cannot handle large-scale training like A100's 40 GB and 312 TFLOPS.

Which is cheaper to rent, the A100 or the RTX A4000?

Cloud rental prices for both the A100 and RTX A4000 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 A4000?

The A100 has 40 to 80 GB of HBM2e memory. The RTX A4000 has 16 GB of GDDR6 memory.

Can I find A100 and RTX A4000 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 A4000?

The A100 uses the Ampere architecture (2020) while the RTX A4000 uses Ampere (2021). The A100 delivers 16.3x the FP16 throughput and 4.6x the memory bandwidth of the RTX A4000.

A100 PCIe 40GB vs RTX A4000: 80GB vs 16GB | GPUPerHour