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Moonshot KimiMoE

Kimi K2 0905 RAM Calculator

Kimi K2 0905 is the September update of [Kimi K2 0711](moonshotai/kimi-k2). It is a large-scale Mixture-of-Experts (MoE) language model developed by Moonshot AI, featuring 1 trillion total parameters with 32...

Standard Recommendation

768GB RAM

Calculated for 4-bit (Q4_K_M) @ 8K Context

1. Select Quantization Level

Quantization compresses model weights to reduce RAM usage, with minor impacts on output quality.

2. Set Target Context Length

Longer contexts require more active memory for the Key-Value (KV) cache.

8,192 tokens
1K tokens32K64K128K tokens

Inference Bandwidth & Speed Matrix

Estimates generation speeds (tokens per second) based on physical memory channel bandwidth constraints.

DDR4 CPU Mode

45 GB/s

0.5 t/s

DDR5 CPU Mode

96 GB/s

1.0 t/s

Mac Unified Memory

300 GB/s

3.0 t/s

GPU VRAM (RTX 4090)

1008 GB/s

5.0 t/s

*Token throughput calculated strictly from weight volume transfers over memory channels. Actual generation speeds can be further throttled by processing threads or VRAM offloading parameters.

Technical Specifications

Total Parameter Count1000 Billion
Active Parameters Per Token100 Billion
Maximum Context Window262K tokens
Primary Framework SupportOllama, llama.cpp, ExLlamaV2, vLLM

GPU & VRAM Sizing Profile

Enterprise GPU Node / Mac Studio 192GB
Est. VRAM Required574.5 GB VRAM
Target GPU HardwareApple Mac Studio (192GB Unified Memory) or Institutional Node (8x H100 / A100)

Hardware Profile: Server-scale deployment. Running this model locally requires extreme unified memory Apple systems or professional multi-GPU servers.

Kimi K2 0905 Memory FAQs

How much RAM does Kimi K2 0905 require?

To run Kimi K2 0905 locally, memory size depends on your selected quantization. At 4-bit compression (Q4_K_M), the weights take up ~562.5GB of RAM. When combined with context cache and OS overhead, a standard **768GB system memory kit** is recommended. Unquantized FP16 execution requires a **1024GB memory setup**.

What are the hardware requirements to run Kimi K2 0905 at FP16 precision?

Running Kimi K2 0905 at unquantized 16-bit precision requires loading ~2000GB of model weights directly into VRAM or system memory. A minimum system memory target of **1024GB RAM** is required to run the weights stably and avoid out-of-memory crashes.

Is Kimi K2 0905 dense or Mixture-of-Experts (MoE)?

Kimi K2 0905 is built on a **MoE** architecture. It has a total of 1000 Billion parameters, but only activates 100 Billion parameters per token. While active parameter sparse execution makes token computing very fast, the entire 1000B parameters must reside in VRAM/RAM for fast expert switching during execution.

How does context window size affect RAM usage for Kimi K2 0905?

Context size directly scales the size of the Key-Value (KV) cache. At a standard 8,192 token context, the KV cache for Kimi K2 0905 uses ~0.25GB. If you scale this to 262.144K tokens, the KV cache can scale past hundreds of GBs, requiring multi-GPU or workstation-class RAM configurations.