Specifications Compared
| Spec | A100 | RTX-4090 |
|---|---|---|
| TDP | 400W | 450W |
| VRAM | 40-80 GB | 24 GB |
| CUDA Cores | 6,912 | 16,384 |
| Memory Type | HBM2e | GDDR6X |
| Architecture | Ampere | Ada Lovelace |
| Form Factors | SXM4, PCIe | PCIe |
| Interconnect | NVLink, PCIe 4.0, InfiniBand | PCIe 4.0 |
| Tensor Cores | 432 | 512 |
| FP16 Performance | 312 TFLOPS | 165 TFLOPS |
| FP32 Performance | 19.5 TFLOPS | 82.6 TFLOPS |
| FP64 Performance | 9.7 TFLOPS | 1.3 TFLOPS |
| INT8 Performance | 624 TOPS | 660 TOPS |
| Memory Bandwidth | 2,039 GB/s | 1,008 GB/s |
Performance Analysis
FP16 performance favors the A100 at 312 TFLOPS over RTX 4090's 165 TFLOPS: this advantage accelerates mixed-precision training common in deep learning. Conversely, RTX 4090 dominates FP32 workloads with 82.6 TFLOPS compared to A100's 19.5 TFLOPS, benefiting simulations requiring single-precision arithmetic. For inference, RTX 4090's FP8 at 660 TFLOPS enables high-throughput low-precision serving unavailable on A100.
Memory specs impact real-world usage profoundly: A100's 40 GB HBM2e VRAM and 2039 GB/s bandwidth allow larger batch sizes and complex models than RTX 4090's 24 GB GDDR6X and 1008 GB/s. Higher bandwidth reduces bottlenecks in data-intensive tasks like LLM training, where A100 sustains throughput for extended sequences. Lower RTX 4090 bandwidth limits scalability for very large batches but suffices for many inference scenarios.
Power consumption remains comparable at 400W TDP for A100 and 450W for RTX 4090: however, A100's SXM4 form factor and NVLink enable efficient multi-node clusters, outperforming RTX 4090's PCIe in scaled environments.
Live Cloud Pricing
Real-time prices from 25+ providers. Updated every 60 seconds.
A100 SXM4 40GB
| Provider | GPU Model | VRAM | Host Specs | Region | Price | Status | Action | |
|---|---|---|---|---|---|---|---|---|
 Vast.ai | NVIDIA A100 SXM4 80GB 80GB VRAM | 80GB | 256 vCPU 63GB RAM 2826GB Storage | Slovenia | $0.73/GPU/hr | Available | ||
Vast.ai | 2×NVIDIA A100 SXM4 80GB 80GB VRAM | 80GB | 256 vCPU 126GB RAM 794GB Storage | Slovenia | $0.73/GPU/hr $1.47/hr total (2×) | Available | ||
 LeaderGPU | 8×NVIDIA A100 PCIe 80GB 80GB VRAM | 80GB | 64 vCPU 384GB RAM 2000GB Storage | Netherlands | $0.90/GPU/hr $7.20/hr total (8×) | Available | ||
Vast.ai | NVIDIA A100 SXM4 80GB 80GB VRAM | 80GB | 64 vCPU 63GB RAM 646GB Storage | Czechia | $1.07/GPU/hr | Available | ||
 Denvr | 8×NVIDIA A100 SXM4 80GB 80GB VRAM | 80GB | 128 vCPU 1024GB RAM 15200GB Storage | Virginia | $1.15/GPU/hr $9.20/hr total (8×) |
RTX 4090
| Provider | GPU Model | VRAM | Host Specs | Region | Price | Status | Action | |
|---|---|---|---|---|---|---|---|---|
 TensorDock | NVIDIA GeForce RTX 4090 24GB VRAM | 24GB | 0 vCPU 0GB RAM | Chubbuck, Idaho | $0.39/GPU/hr | Available | ||
Vast.ai | NVIDIA GeForce RTX 4090 24GB VRAM | 24GB | 64 vCPU 101GB RAM 140GB Storage | Iceland | $0.44/GPU/hr | Available | ||
Vast.ai | NVIDIA GeForce RTX 4090 24GB VRAM | 24GB | 32 vCPU 88GB RAM 106GB Storage | Iceland | $0.47/GPU/hr | Available | ||
TensorDock | NVIDIA GeForce RTX 4090 24GB VRAM | 24GB | 0 vCPU 0GB RAM | Orlando, Florida | $0.48/GPU/hr | Available | ||
Vast.ai | NVIDIA GeForce RTX 4090 24GB VRAM | 24GB | 32 vCPU 101GB RAM 108GB Storage | Iceland | $0.53/GPU/hr | Available |
When to Choose the A100 SXM4 40GB
The A100 SXM4 40GB excels in large-scale LLM training and multi-GPU workflows: 40 GB VRAM accommodates massive models, while 2039 GB/s bandwidth and 312 TFLOPS FP16 speed convergence. NVLink interconnect supports seamless scaling across nodes, unavailable on RTX 4090.
When to Choose the RTX 4090
The RTX 4090 suits cost-sensitive single-GPU tasks like inference or fine-tuning: it delivers 660 TFLOPS FP8 and starts at $0.16 per hour, far below A100's $1.00. Higher 82.6 TFLOPS FP32 aids scientific computing or creative workloads such as Stable Diffusion.
Use Cases
A100's 40 GB VRAM and 312 TFLOPS FP16 handle large models and batches better than RTX 4090's 24 GB and 165 TFLOPS. Higher 2039 GB/s bandwidth minimizes data stalls during training.
RTX 4090's 660 TFLOPS FP8 optimizes low-precision serving at $0.16 per hour start. It suffices for most inference with 24 GB VRAM.
A100 supports bigger datasets via 40 GB VRAM; RTX 4090 offers cost savings at average $0.46 per hour for smaller models.
RTX 4090's Ada architecture and 82.6 TFLOPS FP32 accelerate image generation tasks efficiently.
RTX 4090's 82.6 TFLOPS FP32 surpasses A100's 19.5 TFLOPS for FP32-dominant simulations.
Frequently Asked Questions
Which GPU has more VRAM, A100 or RTX 4090?▾
The A100 SXM4 40GB provides 40 GB HBM2e VRAM, exceeding RTX 4090's 24 GB GDDR6X. This enables larger models on A100. Bandwidth also favors A100 at 2039 GB/s over 1008 GB/s.
Is RTX 4090 cheaper than A100 in the cloud?▾
RTX 4090 starts at $0.16 per hour with an average of $0.46 across 111 offers, much lower than A100's $1.00 start and $2.45 average across 7 offers. This makes RTX 4090 ideal for budget tasks.
Which is better for LLM training?▾
A100 outperforms with 312 TFLOPS FP16 and 40 GB VRAM versus RTX 4090's 165 TFLOPS and 24 GB. NVLink aids multi-GPU training on A100.
Can RTX 4090 handle Stable Diffusion well?▾
RTX 4090 excels due to 82.6 TFLOPS FP32 and Ada architecture optimized for graphics. Its 24 GB VRAM supports high-resolution generations.
What about multi-GPU support?▾
A100 SXM4 includes NVLink and InfiniBand for efficient scaling, unlike RTX 4090's PCIe 4.0 only. This favors A100 for clusters.
How do FP32 performances compare?▾
RTX 4090 leads at 82.6 TFLOPS FP32 over A100's 19.5 TFLOPS. This benefits FP32-heavy scientific computing on RTX 4090.
Which is cheaper to rent, the A100 or the RTX 4090?▾
Cloud rental prices for both the A100 and RTX 4090 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 4090?▾
The A100 has 40 to 80 GB of HBM2e memory. The RTX 4090 has 24 GB of GDDR6X memory.
Can I find A100 and RTX 4090 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 4090?▾
The A100 uses the Ampere architecture (2020) while the RTX 4090 uses Ada Lovelace (2022). The A100 delivers 1.9x the FP16 throughput and 2.0x the memory bandwidth of the RTX 4090.