XAI's Colossus: World's Most Powerful AI Training System Unveiled

xAI cluster is now the most powerful AI training system in the world -- but questions remain over storage capacity, power usage and why it's actually called Colossus

Twitters anställda ser ut att få extra långa dagar på kontoret efter ultimatumet från Elon Musk. (Image credit: Getty Images / Carina Johansen) We recently got a glimpse of what $1 billion worth of AI GPUs looks like when Elon Musk shared a brief video tour of Cortex, X's AI training supercomputer currently under construction at Tesla's Giga Texas plant. More recently, Musk took to his social media platform to announce that Colossus, a new 100k H100 training cluster, is now up and running. Musk claims that Colossus is "the most powerful AI training system in the world" and that it was built "from start to finish" in just 122 days. That's quite an achievement. Servers for the xAI cluster were reportedly provided by Dell and Supermicro, with the cost of the project estimated to be between $3-4 billion. Tom's Hardware notes, "Although all of these clusters are formally operational and even training AI models, it is entirely unclear how many are actually online today. First, it takes some time to debug and optimize the settings of those superclusters. Second, X needs to ensure that they get enough power, and while Elon Musk's company has been using 14 diesel generators to power its Memphis supercomputer, they were still not enough to feed all 100,000 H100 GPUs." The Colossus system is poised to eventually double in capacity, with plans to incorporate an additional 100,000 GPUs - 50,000 H100 units and 50,000 of Nvidia's next-gen H200 chips. The supercluster will primarily be used to train xAI's Grok-3, the company's latest, most advanced AI model. We've yet to see any mention of storage for the new system, but it will need to be huge. The naming of the new supercomputer has raised more than a few eyebrows, however, with people noting that it shares its name with a 1970 sci-fi movie (based on a 1966 novel by D.F. Jones) about a supercomputer that becomes sentient after being given control of the US nuclear arsenal. Things, predictably, go horribly wrong for humanity. Both the novel and film explore timely themes of AI autonomy, the dangers of relinquishing control to machines, and the ethical implications of artificial intelligence. It's possible that Musk wasn't aware of this when the name was chosen for his new AI training system, and it might have been selected purely to emphasize the sheer scale of the supercluster. Then again, with Musk's track record, it wouldn't be surprising if the reference was entirely intentional - he knows exactly what he's doing.

Musk says xAI Colossus is the most powerful AI training system ever

Elon Musk has once again grabbed headlines by giving the world a glimpse of Cortex, X's AI training supercomputer currently under construction at Tesla's Giga Texas plant. In a video that's both awe-inspiring and surreal, Musk showed off what a cool $1 billion in AI GPUs actually looks like. But if that wasn't enough to make tech enthusiasts' jaws drop, Musk recently took to his platform, X, to reveal that the real showstopper -- Colossus, a 100,000 H100 training cluster -- has officially come online. Musk didn't hold back on the bragging rights, claiming that Colossus is "the most powerful AI training system in the world." Even more impressive is the fact that this mammoth project was built "from start to finish" in just 122 days. Considering the scale and complexity involved, that's no small feat. Servers for the xAI cluster were provided by Dell and Supermicro, and while Musk didn't drop an exact number, estimates place the cost between a staggering $3 to $4 billion. Now, here's where things get really interesting. Although the system is operational, it's unclear exactly how many of these clusters are fully functional today. That's not uncommon with systems of this magnitude, as they require extensive debugging and optimization before they're running at full throttle. But when you're dealing with something on the scale of Colossus, every detail counts, and even a fraction of its full potential could outperform most other systems. The future looks even more intense. Colossus is set to double in size, with plans to add another 100,000 GPUs -- split between Nvidia's current H100 units and the highly anticipated H200 chips. This upgrade will primarily power the training of xAI's latest and most advanced AI model, Grok-3, which aims to push the boundaries of what we consider possible in AI.