GoKawiilReddit builder runs Moonshot AI's 2.8T-parameter Kimi K3 on discontinued Intel Optane memory
A homelab enthusiast on Reddit got Moonshot AI's 2.8-trillion-parameter Kimi K3 model running entirely on CPU, using discontinued second-generation Intel Optane PMem 200 modules paired with a 40-core 3rd-gen Xeon Scalable processor instead of a GPU. Using 1-bit quantization, the setup managed just 0.85 tokens per second and required active cooling with dual 12W blower fans aimed directly at the memory modules. It follows an earlier similar project that used first-generation Optane memory in Memory Mode rather than the App Direct Mode used here.
GoKawiil's interpretation of the reporting above, not reported fact.
Kimi K3 demands over 610GB of RAM even at its smallest community-made quantization, far beyond what typical home DRAM setups can affordably provide, especially as DRAM prices have risen sharply. Secondhand Optane memory offers a far cheaper route to that capacity, suggesting enthusiasts are finding workarounds to run massive models locally even though performance remains impractically slow. The experiment also hints that App Direct Mode could let future builders more precisely control where model data resides, potentially improving on Memory Mode results.
- A Redditor ran a 2.8-trillion-parameter model on CPU-only hardware using discontinued Optane PMem 200 memory.
- The setup achieved only 0.85 tokens per second and needed dedicated fan cooling for the memory modules.
- Secondhand Optane offers a cheaper path to the massive RAM capacity large AI models require, as DRAM prices climb.
Noctua NF-A4x20 5V Blower Fan — If you're pushing Optane PMem modules or dense RAM setups like this homelabber, active cooling isn't optional—it's survival gear for your DIMMs. These compact high-static-pressure blower fans are a favorite among homelab and server builders for directing concentrated airflow exactly where memory modules need it most. They're quiet, reliable, and perfectly suited for mounting in tight server chassis spaces.
See Noctua NF-A4x20 5V Blower Fan on Amazon → Affiliate link — we may earn a commission on purchases, at no extra cost to you. Product picked by AI based on this article; it is not a tested recommendation.Source: tomshardware.com — Shane Downing, 2026-11-08
Published there as: “Homelabber uses second-gen Optane memory sticks to run a 2.8-trillion-parameter AI model on CPU alone”
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