Alexx Forge

Sources

Colossus Ledger only records what can be pointed at. Official pages remain the primary text. Independent trackers are shown when they publish methodology-backed estimates, and they are never mixed into Official.

Tags

  • OfficialDirectly stated by xAI / SpaceXAI
  • ObservedPublic reporting, satellite analysis, or consistent multi-source tracking
  • InferredConservative interpretation of public information — used sparingly

Timeline nodes

  1. May 2024GroundbreakOfficial

    Construction begins at the former Electrolux factory in South Memphis. Empty industrial shell. Public materials later frame this as the start of a 122-day build.

  2. Jul–Sep 2024First cluster onlineOfficial

    First operational training cluster. xAI states 100,000 NVIDIA H100 GPUs were brought online, with a build time of 122 days from an empty building.

  3. Early 2025Doubling completeOfficial

    xAI states the cluster was doubled to 200,000 GPUs in an additional 92 days, described as a single interconnected cluster with a stated roadmap toward 1 million GPUs.

  4. 2025Colossus 2 emergesObserved

    A second campus appears across the Tennessee–Mississippi line in public reporting and statements (often referred to as Colossus 2 / Macrohard), with higher-density GPU generations.

  5. Jan 2026Gigawatt-scale claimsObserved

    Public statements describe Colossus 2 as operational at gigawatt training scale, with further upgrades discussed. Independent trackers publish estimates that vary by methodology — shown here as observed, not official counts.

  6. May 2026Colossus 1 leasedOfficial

    SpaceXAI announces an agreement providing Anthropic access to all compute capacity at Colossus 1. Subsequent public remarks describe the lease as short-term rather than multi-year.

  7. Jul 30, 2026Turbine transitionOfficial

    Official Memphis update: agreed order to remove 69 temporary mobile turbines (begin as early as August 2026, complete by July 2027). Permanent 1.2 GW plant with 41 turbines is under construction under a Clean Air Act permit.

  8. Aug 2026Current public stateObserved

    Multi-building complex. Colossus 1 reported as fully leased. Colossus 2 described as the primary training site with multiple models in training. Power generation is in a documented transition from temporary turbines to a permanent plant.

Curated statements

  • 2025 · xAI / SpaceXAI

    Built in 122 days — then doubled in 92 days to 200k GPUs. This is just the beginning.

  • Jan 2026 · Elon Musk

    The Colossus 2 supercomputer for Grok is now operational. First gigawatt training cluster in the world.

  • May 6, 2026 · SpaceXAI

    SpaceXAI will provide Anthropic with access to Colossus 1, one of the world’s largest and fastest-deployed AI supercomputers.

  • May 2026 · Elon Musk

    We have many great Grok models training simultaneously in Colossus 2.

  • May 18, 2026 · Elon Musk

    Cursor Composer 2.5 — partially trained on Colossus 2.

  • May 28, 2026 · Elon Musk

    Colossus 1 lease described as 180 days with 90-day mutual cancellation — not a multi-year commitment.

  • Jul 30, 2026 · SpaceXAI Memphis

    Agreed order to remove all 69 temporary mobile turbines by July 2027 as the 1.2 GW permanent plant comes online.

Back to the Ledger