The NVIDIA V100 defined enterprise AI from 2017 to 2020. It introduced Tensor Cores, pushed deep learning past the 100 TFLOPS barrier, and became the default GPU for training everything from ResNet to BERT.
Then the A100 arrived in 2020 and doubled the memory bandwidth, tripled the Tensor Core performance, and added features: Multi-Instance GPU, structural sparsity, and third-generation NVLink. These capabilities the V100 simply cannot match.
But the V100 is still everywhere. Cloud providers list it at half the price of an A100, and for many workloads, the older GPU delivers perfectly adequate throughput. So which one should you actually deploy?
This guide compares the A100 and V100 across architecture, raw specs, real-world training benchmarks, inference throughput, cloud pricing, and workload fit, with concrete data to help you decide.
Architecture: Ampere vs Volta
Volta (V100)
NVIDIA launched the Volta architecture in 2017 as the first GPU designed from the ground up for deep learning. The V100 introduced first-generation Tensor Cores, specialized matrix multiply-accumulate units that accelerated FP16 mixed-precision training by an order of magnitude over Pascal.
Volta also introduced independent thread scheduling, allowing each thread within a warp to maintain its own program counter and call stack. This reduced serialization penalties from divergent execution paths that plagued earlier architectures like Pascal, making the V100 substantially more efficient for complex parallel algorithms.
The V100 shipped in two form factors: SXM2 (300W, NVLink) and PCIe (250W). Both use 12nm FinFET manufacturing with 815mm² die area, one of the largest GPU dies ever produced at the time.
Ampere (A100)
The Ampere architecture, released in 2020, moved to TSMC's 7nm process node, packing 54.2 billion transistors into an 826mm² die. The smaller transistors enabled a generational leap in both compute density and power efficiency.
Key Ampere improvements over Volta include: third-generation Tensor Cores with support for TF32, BF16, FP64, and INT8 data types (Volta's Tensor Cores only supported FP16), structural sparsity that doubles effective throughput for sparse neural networks, Multi-Instance GPU (MIG) for hardware-level GPU partitioning, third-generation NVLink with 600 GB/s bidirectional bandwidth (twice Volta's 300 GB/s), and PCIe Gen 4 support (32 GB/s vs Volta's Gen 3 at 16 GB/s).
The most impactful change for AI workloads is TF32 (TensorFloat-32). This format provides the same numeric range as FP32 but with reduced mantissa precision, delivering up to 10x the training throughput of FP32 on Volta without requiring code changes. Developers get near-FP32 accuracy at near-FP16 speeds.
Full Specifications Comparison
| Specification | A100 80GB SXM | A100 40GB SXM | V100 32GB SXM2 | V100 16GB SXM2 |
|---|---|---|---|---|
| Architecture | Ampere | Ampere | Volta | Volta |
| Process Node | 7nm | 7nm | 12nm | 12nm |
| Transistors | 54.2B | 54.2B | 21.1B | 21.1B |
| CUDA Cores | 6,912 | 6,912 | 5,120 | 5,120 |
| Tensor Cores | 432 (3rd Gen) | 432 (3rd Gen) | 640 (1st Gen) | 640 (1st Gen) |
| VRAM | 80 GB HBM2e | 40 GB HBM2e | 32 GB HBM2 | 16 GB HBM2 |
| Memory Bandwidth | 2,039 GB/s | 1,555 GB/s | 900 GB/s | 900 GB/s |
| Memory Bus | 5,120-bit | 5,120-bit | 4,096-bit | 4,096-bit |
| FP32 (TFLOPS) | 19.5 | 19.5 | 15.7 | 15.7 |
| FP64 (TFLOPS) | 9.7 | 9.7 | 7.8 | 7.8 |
| FP16 Tensor (TFLOPS) | 312 | 312 | 125 | 125 |
| TF32 Tensor (TFLOPS) | 156 | 156 | N/A | N/A |
| INT8 Tensor (TOPS) | 624 | 624 | N/A | N/A |
| Sparsity (FP16) | 624 TFLOPS | 624 TFLOPS | N/A | N/A |
| NVLink Bandwidth | 600 GB/s | 600 GB/s | 300 GB/s | 300 GB/s |
| PCIe | Gen 4 (64 GB/s) | Gen 4 (64 GB/s) | Gen 3 (32 GB/s) | Gen 3 (32 GB/s) |
| Multi-Instance GPU | Up to 7 instances | Up to 7 instances | No | No |
| TDP | 400W | 400W | 300W | 300W |
The numbers that matter most for AI: the A100 delivers 2.5x the FP16 Tensor performance (312 vs 125 TFLOPS) and 2.3x the memory bandwidth (2,039 vs 900 GB/s) compared to the V100 32GB. With structural sparsity enabled, the gap widens to 5x (624 vs 125 TFLOPS).
Training Benchmarks
Raw TFLOPS tell part of the story. Real-world training throughput depends on memory bandwidth, interconnect speed, software optimizations, and model architecture. Here's how the GPUs compare on actual workloads.
Single-GPU Training Speedups
| Workload | A100 vs V100 Speedup | Notes |
|---|---|---|
| FP32 training (general) | 3.4x | Measured across mixed model types |
| ResNet-50 (FP16) | Up to 7.8x | A100: 2,000+ img/s vs V100: ~400 img/s |
| BERT-Base fine-tuning | 2.4x | FP16 mixed-precision |
| BERT-Large pre-training | 2.5x | FP16 Tensor Cores |
| GPT-2 training | 1.95–2.5x | Varies with sequence length |
| Language model inference | Up to 249x vs CPU | A100 inference benchmark (BERT) |
The biggest gains appear in computer vision. ResNet-50 training sees nearly 8x improvement because the A100's Tensor Cores, wider memory bus, and TF32 support all compound. Language models show a more modest 2–2.5x speedup, where memory bandwidth becomes the bottleneck for attention-heavy architectures.
Multi-GPU Scaling
| Configuration | FP32 Speedup vs 1x V100 |
|---|---|
| 1x V100 | 1.0x (baseline) |
| 1x A100 | 3.4x |
| 8x A100 (mixed precision) | 42.6x |
| 8x V100 (mixed precision) | ~14x |
Multi-GPU A100 clusters scale more efficiently than V100 clusters thanks to NVLink 3.0's doubled bandwidth (600 versus 300 GB/s) and NVSwitch's all-to-all connectivity. In DGX configurations, eight A100s communicate at an aggregate 4.8 TB/s, versus 2.4 TB/s for eight V100s.
Memory and Model Capacity
VRAM determines the largest model you can train or serve on a single GPU. This is one of the A100's most decisive advantages.
| Model | Parameters | VRAM Needed (FP16) | V100 32GB | A100 40GB | A100 80GB |
|---|---|---|---|---|---|
| ResNet-152 | 60M | ~4 GB | Yes | Yes | Yes |
| BERT-Large | 340M | ~2 GB | Yes | Yes | Yes |
| GPT-2 XL | 1.5B | ~3 GB | Yes | Yes | Yes |
| LLaMA 7B | 7B | ~14 GB | Yes (tight) | Yes | Yes |
| LLaMA 13B | 13B | ~26 GB | No | Yes (tight) | Yes |
| Mistral 7B (FP16 + KV) | 7B | ~20 GB | Yes (tight) | Yes | Yes |
| Llama 3.1 70B (INT4) | 70B | ~35 GB | No | No | Yes |
The V100 32GB is adequate for models up to about 7B parameters in FP16. The A100 80GB doubles that capacity and enables quantized 70B models that simply cannot fit on a V100. For training, the gap is even wider because optimizer states (Adam requires 2x the model weight memory) and activations consume additional VRAM.
Multi-Instance GPU (MIG)
MIG is an A100-exclusive feature that partitions a single GPU into up to seven isolated instances, each with dedicated VRAM, L2 cache, and compute resources. The V100 has no equivalent.
A100 80GB MIG Profiles
| Profile | GPU Memory | Compute (SMs) | Use Case |
|---|---|---|---|
| 1g.10gb | 10 GB | 1/7 of GPU | Small model inference, dev/test |
| 2g.20gb | 20 GB | 2/7 of GPU | Medium model inference |
| 3g.40gb | 40 GB | 3/7 of GPU | Large model inference, fine-tuning |
| 7g.80gb | 80 GB | Full GPU | Full training workloads |
MIG is particularly valuable for inference serving, where a single A100 can simultaneously serve multiple small models to different users with hardware-level isolation. A cloud provider can run seven separate inference workloads on one A100, each with guaranteed QoS, something that requires seven separate V100s to achieve.
For teams running mixed workloads (development, inference, and training on the same GPU pool), MIG can improve utilization from a typical 30–40% to 80%+ by eliminating idle GPU capacity.
Inference Performance
For production inference, the A100 introduces data types and features that the V100 cannot access.
| Capability | A100 | V100 |
|---|---|---|
| FP16 inference | 312 TFLOPS | 125 TFLOPS |
| INT8 inference | 624 TOPS | Not supported |
| Structural sparsity | 2x throughput boost | Not supported |
| MIG partitioning | Up to 7 instances | Not supported |
| TF32 inference | 156 TFLOPS | Not supported |
The A100's INT8 support is transformative for inference economics. Many production models (BERT, GPT-2, vision transformers) can be quantized to INT8 with minimal accuracy loss, effectively doubling throughput compared to FP16. Since the V100 lacks native INT8 Tensor Core support, this optimization path is unavailable.
Combined with MIG, a single A100 80GB serving INT8 models can replace 5–7 V100 GPUs for inference workloads, dramatically reducing infrastructure costs.
Cloud Pricing Comparison
The A100 costs more per hour than the V100, but the performance-per-dollar calculation often favors the newer GPU.
| GPU | Typical Cloud Price | VRAM | FP16 Tensor TFLOPS | Price per TFLOPS |
|---|---|---|---|---|
| V100 16GB | $0.80–$1.50/hr | 16 GB | 125 | $0.006–$0.012 |
| V100 32GB | $1.20–$3.06/hr | 32 GB | 125 | $0.010–$0.024 |
| A100 40GB | $1.50–$3.67/hr | 40 GB | 312 | $0.005–$0.012 |
| A100 80GB | $1.80–$5.00/hr | 80 GB | 312 | $0.006–$0.016 |
On specialized GPU cloud providers like Spheron, A100 pricing starts significantly lower than hyperscaler rates. At $1.50 to $2.00/hr for an A100 40GB, the price-per-TFLOPS is roughly half that of a V100 32GB at $3.06/hr on major cloud providers.
Cost-Per-Training-Run Example
Consider training BERT-Large for 1 million steps:
| GPU | Training Time | Cost per Hour | Total Cost |
|---|---|---|---|
| V100 32GB | ~48 hours | $2.50/hr | ~$120 |
| A100 40GB | ~20 hours | $2.00/hr | ~$40 |
| A100 80GB | ~18 hours | $2.50/hr | ~$45 |
The A100 completes the same training run in less than half the time at roughly one-third the cost. The V100 is cheaper per hour but slower per job, which means higher total spend for any non-trivial training workload.
Workload Recommendations
Choose the A100 When
Large model training (7B+ parameters): The A100 80GB is the minimum viable GPU for training or fine-tuning models larger than 7B parameters. The V100's 32GB cap makes it physically impossible to hold these models plus optimizer states.
Production inference at scale: MIG, INT8 support, and structural sparsity give the A100 a 5–7x inference throughput advantage per GPU. For serving workloads with SLA requirements, the A100 is the more cost-effective choice.
Multi-tenant GPU sharing: MIG enables hardware-isolated GPU partitioning that the V100 cannot offer. If multiple teams or services need to share GPU resources with guaranteed performance, the A100 is the only option.
Mixed-precision and INT8 workflows: If your pipeline uses INT8 quantization, TF32, or BF16, the A100's Tensor Cores support these formats natively. The V100 is limited to FP16 and FP32.
Choose the V100 When
Budget-constrained experimentation: For prototyping, hyperparameter searches on small models, or academic research with limited funding, the V100's lower hourly cost makes it a sensible choice. A V100 32GB handles models up to 7B parameters in FP16 without issue.
Legacy workloads: If your training pipeline is already optimized for V100 and you're not bottlenecked by VRAM or throughput, the switching cost may not justify migration. The V100 still delivers strong FP16 Tensor performance at 125 TFLOPS.
Short inference jobs: For batch inference on models under 10B parameters where latency isn't critical, the V100 provides acceptable throughput at a lower per-hour rate. This assumes you don't need MIG or INT8 quantization.
HPC and scientific computing (FP64): The V100 delivers 7.8 TFLOPS of FP64 performance. While the A100's 9.7 TFLOPS is higher, the V100's price-to-FP64-performance ratio can be competitive for double-precision scientific workloads.
V100 to A100 Migration Considerations
If you're currently running V100s and evaluating an upgrade, here are the key factors.
Software Compatibility
The A100 is fully backward-compatible with V100 CUDA code. Any application compiled for compute capability 7.0 (Volta) runs on the A100's 8.0 (Ampere) without changes. However, to access TF32, BF16, sparsity, and MIG, you'll need CUDA 11.0+ and updated framework versions (PyTorch 1.7+, TensorFlow 2.4+).
NVLink and Interconnect
V100 clusters using NVLink 2.0 cannot directly interconnect with A100s using NVLink 3.0. Multi-GPU communication must use the same GPU generation. If you're building a mixed fleet, the GPUs will communicate over PCIe, which is significantly slower than NVLink.
Power and Cooling
The A100 SXM draws 400W compared to the V100 SXM2's 300W, a 33% increase. Ensure your data center's power distribution and cooling capacity can handle the higher thermal load before upgrading. For cloud deployments on Spheron, this is handled by the infrastructure provider.
Phasing Strategy
Many organizations run a hybrid approach: A100s for training and latency-sensitive inference, V100s for batch inference and development. This maximizes ROI from existing V100 hardware while deploying A100s where the performance advantage has the highest business impact.
Deploy on Spheron
Looking for GPU infrastructure to power your AI workloads? Spheron offers bare-metal GPU access with transparent pricing, instant provisioning, and no long-term contracts. Deploy on A100 80GB, H100, H200, and RTX 4090 GPUs with full root access, NVLink support, and pay-per-second billing.
Whether you're training large language models on A100 clusters or running cost-effective inference on V100s, Spheron provides the flexibility to scale up or down without hardware commitments.
Explore GPU options on Spheron →
Frequently Asked Questions
How much faster is the A100 than the V100 for training?
The A100 is 1.95x to 7.8x faster than the V100 depending on the workload. General FP32 training sees about 3.4x improvement. ResNet-50 in FP16 shows the largest gap at nearly 8x, while language models like BERT see 2–2.5x speedups. The exact ratio depends on the model architecture, precision format, batch size, and whether sparsity is leveraged.
Can V100 CUDA code run on the A100 without changes?
Yes. The A100 (compute capability 8.0) is fully backward-compatible with V100 code (compute capability 7.0). However, to access Ampere-specific features like TF32 automatic precision, BF16 Tensor Cores, structural sparsity, and MIG partitioning, you need CUDA 11.0+ and updated deep learning frameworks.
Is the V100 still worth buying in 2025?
For new purchases, the V100 is difficult to justify. The A100 80GB offers 2.5x the VRAM, 2.3x the memory bandwidth, and 2.5x the Tensor Core performance at only a moderately higher hourly cloud rate. On a cost-per-training-run basis, the A100 is typically cheaper. However, existing V100 fleets remain viable for inference on small-to-medium models and budget-constrained experimentation.
What is Multi-Instance GPU (MIG) and why does it matter?
MIG is an A100-exclusive feature that partitions a single GPU into up to seven hardware-isolated instances, each with dedicated VRAM, cache, and compute resources. This enables multi-tenant GPU sharing with guaranteed performance, making it valuable for inference serving, development environments, and cloud providers. The V100 has no equivalent, sharing a V100 between workloads requires software-level time-slicing with no isolation guarantees.
Which GPU is better for inference?
The A100 is significantly better for inference due to INT8 Tensor Core support (624 TOPS vs not available on V100), MIG partitioning for multi-model serving, and structural sparsity. A single A100 80GB can replace 5–7 V100s for production inference workloads, especially when models are quantized to INT8. The V100 is still adequate for batch inference on smaller models where latency is not a concern.
How does memory bandwidth affect AI training performance?
Memory bandwidth determines how quickly the GPU can feed data to its compute units. The A100 80GB delivers 2,039 GB/s versus the V100's 900 GB/s, a 2.3x improvement. For large language models where attention layers are memory-bound rather than compute-bound, this bandwidth advantage translates directly into higher training throughput. It's one of the main reasons the A100 outperforms the V100 by a wider margin on Transformer-based models than on convolutional networks.