How much VRAM does Mixtral 8x22B need?

Mixtral 8x22B (141B parameters) requires approximately 94.2 GB of memory with Q4_K_M quantization.

What is the best quantization for Mixtral 8x22B?

The recommended quantization for Mixtral 8x22B is Q4_K_M, which balances quality and memory efficiency.

Can it run?

No, Mixtral 8x22B requires more memory than Radeon RX 6850M XT 12GB provides.

FWon't run

Too heavy

Using Q4_K_M in llama.cpp

Capabilities:

Fit status

Too heavy

Decode

6.9 tok/s

TTFT

27907 ms

Safe context

Memory

94.2 GB / 12.0 GB

Weights86.0 GB

KV Cache6.1 GB

Runtime0.9 GB

Headroom1.2 GB

Workload	Grade	Fit	Decode	TTFT	Context
Agentic Coding	F	Too heavy	5.4 tok/s	52189 ms	4K
Chat	F	Too heavy	5.4 tok/s	19571 ms	4K
Coding	F	Too heavy	6.9 tok/s	27907 ms	4K
RAG	F	Too heavy	5.4 tok/s	65236 ms	4K
Reasoning	F	Too heavy	5.4 tok/s	42403 ms	4K

How Mixtral 8x22B (141B params) fits at each quantization level on Radeon RX 6850M XT 12GB (12.0 GB usable).

Quant	Bits	VRAM	Quality	Fit
Q2_K	2	55.0 GB	Low	F0
Q3_K_S	3	69.1 GB	Low	F0
NVFP4	4

Upgrade options

MacBook Pro M3 Max 128GBBest value

D5.1 tok/s decode

~$2,499 MSRP

AMD Instinct MI350X 288GBBudget pick

C130.3 tok/s decode

~$8,000 MSRP