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Models· 3 min

What is Mixture of Experts (MoE)?

MoE models have many specialist sub-networks but activate only a few per token — big brain, small bill.

Key idea

A router picks the top-k 'experts' for each token, so a 400B-parameter model may only use ~40B per forward pass.

Example

Mixtral 8x7B, DeepSeek-V3 and rumored GPT-4 all use MoE to boost capacity without proportional cost.

What to remember

  • Better capability-per-FLOP than a dense model
  • Harder to serve — experts must be sharded across GPUs
  • Training stability requires load-balancing tricks