xAI’s Colossus 2 – First Gigawatt Datacenter In The World, Unique RL Methodology, Capital Raise
SemiAnalysis Jeremie Eliahou Ontiveros
xAI is building Colossus 2, a gigawatt-scale datacenter in Memphis with power infrastructure in Mississippi, which it constructed in six months by partnering with Solaris Energy Infrastructure to deploy over 1.1 gigawatts of gas turbine capacity. The company expects to have over 110,000 GB200 NVL72 GPUs operational by Q2 2027, surpassing Meta and Anthropic's clusters and requiring tens of billions in capital funding potentially from Middle Eastern investors. This scale-up positions xAI to maintain its position in frontier AI development and potentially deploy additional datacenters in Saudi Arabia using a capital raise rumored at $40 billion.
Why it matters
Much has been written about xAI’s Colossus 1. The Memphis build belongs in the history books: the largest AI training cluster, erected from scratch in 122 days. With roughly 200,000 H100/H200s and ~30,000 GB200 NVL72, it remains, today, the largest fully operational, single-coherent cluster (setting apart Google, master of multi-datacenter-training). However, Colossus 1’s ~300 MW […]
