Colossus 2, xAI's second Memphis supercomputer, is running and the company says it will train Grok 5, the next version of its chatbot. On an October 20 earnings call, Elon Musk said SpaceX, xAI's parent since this year's merger, is adding roughly 200,000 Nvidia GB300 chips a month.
A federal judge on October 19 let the United States join a Clean Air Act lawsuit over the gas turbines that power the site, but refused to throw the case out. Musk has said Colossus 2 should hold about 1.21 million Nvidia chips by late December, and the company is targeting 2.5 to 3 gigawatts of computing capacity by the end of 2026.
Why it matters
xAI is betting more than a million Nvidia chips can make Grok a frontier model, and its power supply is now in federal court.
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Key Indicators
1.44M
Combined GPU target
Colossus 1 and 2 combined, counting three 220,000-chip tranches Musk says could land by late December 2026.
1.2 GW
Dedicated power plant capacity
Permanent gas plant under construction in Southaven, Mississippi; state regulators granted an air permit in March 2026.
2.5-3 GW
Compute target for end of 2026
Musk's figure on the October 20 earnings call; he said 10 more gigawatts would follow in 2027.
440,000
GB300 GPUs in use
In use at Colossus 2 as of late September 2026, alongside 110,000 GB200s.
660,000
Additional GPUs expected
Three 220,000-chip tranches due by end of 2026; the December batch is conditional on Musk's 'if we get lucky.'
122 days
Colossus 1 build time
Time to stand up the first 100,000 H100 GPUs in 2024.
1 GW
Campus IT load reached
Colossus campus near Memphis hit roughly 1 gigawatt of IT load in early October 2026. Colossus 2 alone draws about 946 MW.
15 events
Latest: October 20th, 2026 · 3 weeks ago
Showing 8 of 15
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October 2026
Musk sets 200,000-chip monthly pace and 13 GW target
LatestStatement
On SpaceX's quarterly earnings call, Musk said the company is tracking about 200,000 GB300 GPUs a month through 2026 and into 2027, expects 2.5 to 3 gigawatts online by year-end, and would be surprised to finish 2027 below 13 gigawatts.
Judge lets U.S. join clean-air suit, keeps case alive
Legal
U.S. District Judge Debra M. Brown allowed the federal government to intervene in the NAACP's Clean Air Act case over the Southaven gas plant but denied its motion to dismiss.
Grok Enterprise launched for large companies
New Capabilities
xAI opened Grok Enterprise, a private-model tier for Fortune 500 companies with isolated instances and zero data retention, using Colossus 2's capacity for low-latency inference.
Colossus 2 brought online
Milestone
xAI brings Colossus 2 online, roughly doubling training compute for Grok.
Colossus campus reaches 1 GW of IT load
Milestone
The campus near Memphis hit roughly 1 gigawatt of IT load in early October, which SemiAnalysis calls a first for a single-site data center. Colossus 2 alone draws about 946 MW.
September 2026
440,000 GB300 GPUs in use
Milestone
440,000 GB300 GPUs in use at Colossus 2, with 660,000 more expected by year-end.
June 2026
Google rents GPUs from SpaceX
Deal
Google agrees to rent about 110,000 GPUs from SpaceX for $920 million monthly.
Justice Department moves to dismiss lawsuit
Legal
DOJ moves to intervene and dismiss the environmental lawsuit, citing national security.
May 2026
Anthropic rents Colossus 1 capacity
Deal
Anthropic agrees to rent essentially all compute capacity at Colossus 1.
April 2026
Environmental lawsuit filed
Legal
NAACP, SELC, and Earthjustice sue xAI and MZX Tech over unpermitted turbines.
March 2026
Gas plant permit approved
Regulatory
Mississippi regulators permit a gas plant for the site; October 2026 reporting describes an air permit covering 27 gas-powered turbines.
January 2026
Musk declares Colossus 2 operational
Statement
Elon Musk says Colossus 2 is operational, with 1.5 gigawatts planned for April.
First GPU cluster comes online
Milestone
About 110,000 Nvidia GB200 processors come online after a reported 91-day build.
August 2025
Cooling infrastructure installed
Construction
119 air-cooled chillers on site, roughly 200 megawatts of cooling capacity.
February 2025
xAI buys Memphis warehouse site
Acquisition
xAI affiliate purchases warehouse at 5420 Tulane Road for about $80 million.
Scenarios
1
Colossus 2 hits 1.21 million GPUs by year-end
Possible
Resolves by Jan 15, 2027
Discussed by: xAI's roadmap, reported by AIReport.NET and Compute Atlas
xAI has scheduled three tranches of about 220,000 GB300 GPUs each, landing by end of October, November, and December. If all land on time, Colossus 2 alone would hold about 1.21 million chips, and the combined fleet including Colossus 1 would reach about 1.44 million.
2
Expansion falls short as chip deliveries slip
Possible
Resolves by Jan 15, 2027
Discussed by: Skeptics cited by AIReport.NET
Chip deliveries slip, transformers and switchgear are back-ordered, and power projects face permitting delays. The 1.44 million figure is best read as a ceiling rather than a promise.
3
Environmental lawsuit reshapes the buildout
Uncertain
Resolves by Jul 1, 2027
Discussed by: NAACP, Southern Environmental Law Center, Earthjustice
The federal lawsuit over unpermitted turbines in Southaven could force changes to how xAI powers the cluster. The Justice Department moved to dismiss the case in June 2026, arguing national security interests, but the case remains pending.
4
Grok Enterprise wins major Fortune 500 customers
Possible
Resolves by End of 2026
Discussed by: All Things Elon, xAI's launch announcement
Grok Enterprise offers private, isolated model instances with zero data retention to large companies. xAI built the tier on Colossus 2's added compute, which gives it the room to promise low latency and steady throughput. The offering targets companies that want frontier models without sending data outside their walls.
5
Grok 5 ships trained on Colossus 2
Possible
Resolves by End of 2027
Discussed by: xAI, as reported by All Things Elon
xAI says Colossus 2 will train Grok 5, promising sharper reasoning, stronger coding and better handling of images and audio. A release would be the first public test of whether the added chips show up in the model.
Historical Context
2 moments from history that rhyme with this story — and how they unfolded.
1 of 2
December 1943 - June 1944
Colossus (1943-1944)
British engineers at Bletchley Park built the world's first programmable electronic computer in under a year. Named Colossus, it was designed to break the Lorenz cipher used by German high command, processing 5,000 characters per second.
Then
Colossus helped break German military communications, contributing to Allied victories including D-Day.
Now
It established the template for electronic computing, though its existence remained secret until the 1970s.
Why this matters now
The name is the same, and so is the pattern: a machine built in months, at unprecedented speed, to gain a decisive advantage. xAI's Colossus 2 follows that playbook in the AI race.
2 of 2
June 1942 - August 1945
Manhattan Project (1942-1945)
The U.S. government compressed a multi-year research program into three years, building massive industrial facilities at Oak Ridge, Tennessee and Hanford, Washington. The project employed 130,000 people and cost about $2 billion, roughly $30 billion in today's dollars.
Then
The project produced the first atomic weapons, used at Hiroshima and Nagasaki in August 1945.
Now
It established the model for large-scale, time-compressed government and industrial projects.
Why this matters now
Like the Manhattan Project, Colossus 2 compresses timelines and builds massive industrial infrastructure in a single region. The speed of construction and its local impacts are central to both stories.
