How much VRAM does Mixtral 8x22B need?

Mixtral 8x22B (141B parameters) requires approximately 93.8 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 RX 6650 XT 8GB provides.

FWon't run

Too heavy

Using Q4_K_M in llama.cpp

Capabilities:

Fit status

Too heavy

Decode

4.5 tok/s

TTFT

43056 ms

Safe context

Memory

93.8 GB / 8.0 GB

Weights86.0 GB

KV Cache6.1 GB

Runtime0.9 GB

Headroom0.8 GB

Workload	Grade	Fit	Decode	TTFT	Context
Agentic Coding	F	Too heavy	3.2 tok/s	88414 ms	4K
Chat	F	Too heavy	3.2 tok/s	33155 ms	4K
Coding	F	Too heavy	4.5 tok/s	43056 ms	4K
RAG	F	Too heavy	3.2 tok/s	110518 ms	4K
Reasoning	F	Too heavy	3.2 tok/s	71836 ms	4K

How Mixtral 8x22B (141B params) fits at each quantization level on RX 6650 XT 8GB (8.0 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