OpenAI's gargantuan data center is even bigger than Elon Musk's xAI Colossus — world's largest 300 MW AI data center could reach record 1 gigawatt scale by next year, threatens grid stability

Data center image
(Image credit: Getty / Yuichiro Chino)

Elon Musk's xAI made quite a splash when it built a data center with 200,000 GPUs that consumes approximately 250 MW of power. However, it appears that OpenAI has an even larger data center in Texas, which consumes 300 MW and houses hundreds of thousands of AI GPUs, details of which were not disclosed. Furthermore, the company is expanding the site, and by mid-2026, it aims to reach a gigawatt scale, according to SemiAnalysis. Such gargantuan AI clusters are creating challenges for power companies not only in power generation but also in power grid safety.

OpenAI appears to operate what is described as the world's largest single data center building, with an IT load capacity of around 300 MW and a maximum power capacity of approximately 500 MW. This facility includes 210 air-cooled substations and a massive on-site electrical substation, which further highlights its immense scale. A second identical building is already under construction on the same site as of January 2025. When completed, this expansion will bring the total capacity of the campus to around a gigawatt, a record.

Anton Shilov
Contributing Writer

Anton Shilov is a contributing writer at Tom’s Hardware. Over the past couple of decades, he has covered everything from CPUs and GPUs to supercomputers and from modern process technologies and latest fab tools to high-tech industry trends.