A100 40GB — Specs, Rank & Tuning
NVIDIA Datacenter Ampere · Ampere · 2020 · Upper mainstream (tier 72/100) · 40 GB HBM2e
A100 40GB — key specifications
| Brand / series | NVIDIA Datacenter Ampere |
|---|---|
| Architecture / class | Ampere |
| Launch year | 2020 |
| Memory | 40 GB HBM2e · 5120-bit · 1555 GB/s |
| Boost clock | 1410 MHz |
| FP16 compute | 77.97 TFLOPS |
| Interconnect | PCIe 4.0 |
| TDP | 400 W |
| Relative tier | 72/100 — Upper mainstream |
Specs: vendor datasheets / TechPowerUp database, retrieved 2026-08-29. Tier is a TweakGearPro relative performance index (estimate), not a benchmark guarantee.
Relative performance estimate
TweakGearPro anchors the ai gpu category to its flagship (highest tier) and expresses A100 40GB as an estimated percentage of that flagship, derived from the relative-performance index (tier 0–100). Planning estimate, not a benchmark.
| AI GPU (nearby tier) | Tier /100 | Est. relative perf. |
|---|---|---|
| RTX 6000 Ada | 84 | 84% |
| H20 (China) | 82 | 82% |
| NVIDIA L40S 48GB | 80 | 80% |
| GeForce RTX 4090 | 78 | 78% |
| A100 80GB | 78 | 78% |
| A800 80GB (China) | 78 | 78% |
| A100 40GB (this part) | 72 | 72% |
Method: relative performance % = (part tier ÷ flagship tier) × 100, using the TweakGearPro tier index built from public benchmark / spec-class data. Source: vendor datasheets / TechPowerUp database, retrieved 2026-08-29. Real-world performance varies by workload, drivers and cooling.
Build compatibility & pairing guidance
Practical build notes derived from this part's dataset fields and TweakGearPro reference constants. Planning guidance, not purchase advice.
| Estimated system PSU | ≈ 750 W (this part's 400 W TDP + ~200 W system overhead, with 20% headroom). Confirm with the PSU Wattage Calculator. |
|---|---|
| Cooler / thermal | Plan cooling rated above this part's 400 W TDP; typical desktop safe ceiling is ~90°C (TweakGearPro reference). Check the Thermal Headroom tool. |
| Pairing balance | Match with a CPU whose tier is within ~20 of this part's tier (72/100) to avoid a bottleneck. Run the Bottleneck Estimator. |
| VRAM fit | 40 GB HBM2e — for gaming/ML sizing see the VRAM Recommendation tool or the LLM planner below. |
Reference constants (PSU headroom 20%, safe CPU/GPU ceiling 90°C) from the TweakGearPro PC reference dataset, retrieved 2026-08-29. Adapter/case clearance and exact board power vary by model — verify with vendor datasheets.
Tune & power-plan your build
Input your cooling, case airflow and goal to generate a printable tuning sheet, or size your whole-system PSU.
LLM deployment planner
VRAM math is an estimate — KV-cache sizing depends on context length and implementation.
My deployment plan — A100 40GB
Good fit for local/edge inference. Expect ~667% of weights+KV to fit with INT4 quantization. Generated at TweakGearPro · 2026-09-13
Release & generational notes
A100 40GB launched in 2020 on the Ampere architecture as part of the Datacenter Ampere family, sitting at tier 72/100 (Upper mainstream).
| Series | Datacenter Ampere |
|---|---|
| Architecture | Ampere |
| Launch year | 2020 |
| Successor | A800 80GB (China) (2022, tier 78/100) |
In the Datacenter Ampere series
Generational context is summarized from official release year and architecture only; TweakGearPro does not invent patch or refresh dates. For the full generational ranking, see the AI-GPU Tier List (LLM).
Related hardware to compare
Same-tier peers plus a pairing from another category — open any profile.
Sources & methodology
- Specifications: vendor datasheets (NVIDIA, AMD, Intel, Samsung, WD, Crucial, Corsair, Seagate, Noctua, ASUS, LG, Dell and others) and the TechPowerUp database, retrieved 2026-08-29.
- Relative-performance index: TweakGearPro estimate built from public benchmark / spec-class data; flagship-anchored percentages are planning estimates, not measured scores.
- Reference constants (PSU headroom, safe thermal ceiling) from the TweakGearPro PC reference dataset, retrieved 2026-08-29.
- Tuning, PSU and VRAM figures are planning estimates — verify with your own stress tests and the component vendor's documentation.
How this page's estimates are computed
The relative-performance percentage anchors the category flagship (highest tier) at 100 and scales each part by its tier ratio. The estimated system PSU adds a base system overhead to the part's TDP and applies a 20% headroom from the reference dataset, rounded to a common PSU rating. The tuning sheet estimates load temperature from TDP, cooling class and case airflow, then suggests a voltage offset and expected clock delta — always confirm with a stress test. The LLM planner converts model parameters and quantization to an approximate VRAM footprint (weights + KV-cache) and divides by the card's usable VRAM to suggest a card count. None of these outputs are benchmark guarantees. For non-CPU/GPU parts the tier reflects the part's spec class relative to the best current model in that category.