A40 vs RTX A4000

AmperevsAmpereUpdated 35 days ago

The A40 emerges as the superior choice for most AI and compute workloads due to its 48 GB VRAM, 37.4 TFLOPS performance, and 696 GB/s bandwidth, enabling larger models and faster training than the RTX A4000's 16 GB and 19.2 TFLOPS. Despite higher $1.29 per hour average cost, its capabilities justify selection for production-scale tasks over the budget-oriented A4000.

A40 from $0.08/hrRTX A4000 from $0.08/hr

Specifications Compared

SpecA40RTX-A4000
TDP300W140W
VRAM48 GB16 GB
CUDA Cores10,7526,144
Memory TypeGDDR6GDDR6
ArchitectureAmpereAmpere
Form FactorsPCIePCIe
InterconnectNVLink
Tensor Cores336192
FP16 Performance37.4 TFLOPS19.2 TFLOPS
FP32 Performance37.4 TFLOPS19.2 TFLOPS
FP64 Performance0.6 TFLOPS
INT8 Performance299 TOPS
Memory Bandwidth696 GB/s448 GB/s

Performance Analysis

The A40 outperforms the RTX A4000 across key metrics, doubling FP16 and FP32 throughput at 37.4 TFLOPS versus 19.2 TFLOPS. This delta translates to faster model training and inference: training large neural networks benefits from the A40's superior compute, reducing epochs by approximately half in FP16-optimized frameworks like TensorFlow. Inference workloads see similar gains, with the A40 processing more queries per second on memory-bound tasks.

Memory capacity defines the real-world divide: 48 GB on the A40 supports batch sizes up to three times larger than the A4000's 16 GB limit, critical for stable training of models exceeding 10 billion parameters. Bandwidth reinforces this: 696 GB/s on the A40 minimizes data starvation during gradient updates, enabling 55 percent higher throughput than the A4000's 448 GB/s in bandwidth-intensive simulations. Lower TDP on the A4000 aids dense deployments, but A40's NVLink accelerates multi-GPU synchronization for distributed training.

Power efficiency favors the A4000 at 140W, yielding better perf-per-watt for lighter loads, yet A40's raw specs dominate heavy AI pipelines where compute and memory scale linearly with workload demands.

Live Cloud Pricing

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

A40

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

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 A40

Select the A40 for memory-intensive AI training, such as LLMs with over 20 billion parameters, where 48 GB VRAM accommodates full model loading without swapping. Its 696 GB/s bandwidth and NVLink support excel in multi-GPU clusters, cutting training time by leveraging 37.4 TFLOPS per GPU across nodes. Data center deployments benefit from sustained 300W performance on large batch sizes.

When to Choose the RTX A4000

Opt for the RTX A4000 in cost-sensitive environments like prototyping or inference on models under 7 billion parameters, fitting within 16 GB VRAM. At $0.08 per hour starting price, it delivers 19.2 TFLOPS efficiently at 140W, ideal for single-node workstations or edge computing. Lower bandwidth suffices for smaller batches, prioritizing affordability over peak throughput.

Use Cases

LLM Training
A40

A40's 48 GB VRAM handles massive models without fragmentation, while 37.4 TFLOPS doubles training speed over A4000's 16 GB limit.

LLM Inference
A40

Higher 696 GB/s bandwidth on A40 supports larger batches for high-throughput serving; 48 GB fits multiple concurrent models.

Fine-tuning
Either

A4000 suffices for datasets under 16 GB at lower $0.08/hr cost; A40 accelerates with NVLink for distributed fine-tuning.

Stable Diffusion
RTX A4000

RTX A4000's 16 GB VRAM meets image generation needs efficiently at 140W and $0.31/hr average, avoiding A40's overkill.

Scientific Computing
A40

A40's 37.4 TFLOPS FP32 and NVLink enable complex simulations scaling beyond A4000's 19.2 TFLOPS single-node capacity.

Frequently Asked Questions

Which has more VRAM: A40 or RTX A4000?

The A40 provides 48 GB GDDR6 VRAM, three times the RTX A4000's 16 GB. This allows A40 to load larger models for training. Bandwidth follows suit at 696 GB/s versus 448 GB/s.

Is A40 faster than RTX A4000 for AI?

Yes, A40 delivers 37.4 TFLOPS FP16/FP32, double the A4000's 19.2 TFLOPS. Real-world training runs twice as fast on A40. NVLink adds multi-GPU advantages absent in A4000.

What is the price difference between A40 and A4000 in cloud?

A40 starts at $0.24/hr averaging $1.29 across 22 offers; A4000 at $0.08/hr averaging $0.31 across 28 offers. A4000 offers four times lower entry cost. Choose based on workload scale.

Does RTX A4000 support NVLink?

No, RTX A4000 lacks NVLink interconnect, unlike A40. This limits A4000 to PCIe scaling. A40 excels in multi-GPU data center setups.

Which is more power efficient?

RTX A4000 at 140W TDP outperforms A40's 300W in perf-per-watt for light tasks. A40's higher TDP sustains peak 37.4 TFLOPS longer. Efficiency depends on utilization.

Can A4000 replace A40 in workstations?

RTX A4000 works for sub-16 GB models at lower cost, but cannot match A40's 48 GB for large-scale AI. Use A4000 for prototyping. A40 suits production.

Which is cheaper to rent, the A40 or the RTX A4000?

Cloud rental prices for both the A40 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 A40 have compared to the RTX A4000?

The A40 has 48 GB of GDDR6 memory. The RTX A4000 has 16 GB of GDDR6 memory.

Can I find A40 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 A40 and the RTX A4000?

The A40 uses the Ampere architecture (2020) while the RTX A4000 uses Ampere (2021). The A40 delivers 1.9x the FP16 throughput and 1.6x the memory bandwidth of the RTX A4000.