How much VRAM does Qwen3.5 122B A10B need?

Qwen3.5 122B A10B (122B parameters) requires approximately 82.0 GB of memory with Q3_K_M quantization.

What is the best quantization for Qwen3.5 122B A10B?

The recommended quantization for Qwen3.5 122B A10B is Q3_K_M, which balances quality and memory efficiency.

Can it run?

No, Qwen3.5 122B A10B requires more memory than RTX 4000 Ada 20GB provides.

FWon't run

Too heavy

Using Q3_K_M in Ollama

Capabilities:

Fit status

Too heavy

Decode

4.0 tok/s

TTFT

48011 ms

Safe context

Memory

82.0 GB / 20.0 GB

Weights59.8 GB

KV Cache19.1 GB

Runtime1.2 GB

Headroom2.0 GB

Workload	Grade	Fit	Decode	TTFT	Context
Agentic Coding	F	Too heavy	4.4 tok/s	64463 ms	6K
Chat	F	Too heavy	4.4 tok/s	24174 ms	4K
Coding	F	Too heavy	4.0 tok/s	48011 ms	4K
RAG	F	Too heavy	4.4 tok/s	80578 ms	6K
Reasoning	F	Too heavy	4.4 tok/s	52376 ms	4K

How Qwen3.5 122B A10B (122B params) fits at each quantization level on RTX 4000 Ada 20GB (20.0 GB usable).

Quant	Bits	VRAM	Quality	Fit
Q2_K	2	47.6 GB	Low	F0
Q3_K_S	3	59.8 GB	Low	F0
NVFP4	4

Upgrade options

MacBook Pro M3 Max 128GBBest value

C3.7 tok/s decode

~$2,499 MSRP

AMD Instinct MI350X 288GBBudget pick

C90.9 tok/s decode

~$8,000 MSRP

NVIDIA H200 141GBNVIDIA upgrade