Won't fitfp16 · 4K ctx · batch 1

Does A100 40GB run Qwen2.5-72B? No at fp16.

At fp16 precision, Qwen2.5-72B (72 B parameters) needs roughly 164.1 GB of VRAM. A100 40GB only has 40 GB, short by 124.1 GB. INT4 quantization brings it down to 44.6 GB.

410%
VRAM
Won't fit
Estimated VRAM (fp16)
164.1 GB
of 40 GB on A100 40GB· 124.1 GB short
Tok/sec
27
TFTT
2455ms
Power
255W
Rent on GPUniq marketplace
A100 40GB
Live prices from verified providers · billed hourly, no commitment.
Rent now

Memory breakdown (fp16)

Model Weights
144.00 GB
KV Cache
3.75 GB
Activations
15.00 GB
Framework Overhead
1.36 GB

Quantization comparison

Lower precision = less VRAM with a small quality trade-off. Quality order: FP16 > INT8 > INT4.

PrecisionVRAMUtilisationFits on A100 40GB?
FP16 (full precision)164.1 GB410%Won't fit
INT8 (8-bit)84.4 GB211%Won't fit
INT4 / Q4 (4-bit)44.6 GB111%Won't fit

Frequently asked

Can A100 40GB run Qwen2.5-72B?
Not at fp16 — Qwen2.5-72B needs about 164.1 GB while A100 40GB has 40 GB. It fits at INT4 quantization (44.6 GB) with some accuracy trade-off.
How much VRAM does Qwen2.5-72B use?
About 164.1 GB at fp16, 44.6 GB at INT4 (for a 4K context, batch size 1). Longer contexts add to KV cache size; larger batches increase activations.
What's the fastest way to run Qwen2.5-72B on A100 40GB?
Use a production inference engine like vLLM, SGLang, or TensorRT-LLM with paged attention — they cut KV cache 2–3× vs the naive estimate and batch multiple requests efficiently. For A100 40GB, enable Flash Attention 2.
Where can I rent a A100 40GB?
GPUniq aggregates live A100 40GB offers from verified providers. You can deploy an instance in about a minute and pay hourly with no commitment.
Try it live

Chat with Qwen2.5-72B — no setup

Send a prompt and see how Qwen2.5-72B responds directly in our chat. No installation, no GPU required to test.

Open in chat
Want to tweak sequence length, batch size, or fine-tuning? Open the full calculator →
None of the common quantization levels fit this model on A100 40GB. Consider multi-GPU deployment or a larger card.