Nvidia Market Cap Jumps by $177 Billion After OpenAI Announcement

After Nvidia announced that it plans to invest $100 billion into OpenAI, its own market cap increased by $177 billion. Crypto miner stocks rose as this vendor financing deal shored up the AI market.

Still, Nvidia was extremely vague about the timetable for the actual investment, and some economists are skeptical. AI capex is now a cornerstone of the US economy, and one downturn could precipitate broader turmoil.

Nvidia’s OpenAI Investment

AI investment is already growing at a rapid pace, and the industry just got a major shot in the arm. Earlier today, AI chip manufacturer Nvidia announced an eventual $100 billion in OpenAI investments. This caused the firm’s stock price to jump up dramatically:

Nvidia Price Performance. Source: Google Finance

Nvidia isn’t the only firm that jumped from the OpenAI deal; most Bitcoin mining companies saw similar boosts. This isn’t too surprising, as Nvidia is closely entangled with the crypto mining industry.

This massive deal could keep the AI sector and related industries afloat for the foreseeable future.

Nonetheless, the announcement was met with a little incredulity from TradFi commentators. $100 billion is a ludicrous amount of money, and Nvidia’s investing it into one company alone. Still, it makes sense, as OpenAI is a major customer for Nvidia.

Some economists compared the deal to vendor financing, a common practice, but on a larger scale.

AI Capex: A Private Money Printer?

Still, there’s one thing that has engendered a lot of unease. Nvidia had a vague timetable for the OpenAI investment, and no one is certain when this $100 billion payment will actually happen. However, Nvidia’s own market cap rose by $177 billion.

In other words, good vibes were sufficient to spin up these gargantuan profits:

it's cool to announce you're spending $100 billion in cash over some long and vague timeframe and then your market cap goes up by more than $100 billion

— Matthew Zeitlin (@MattZeitlin) September 22, 2025

Simply put, OpenAI executives are concerned about a bubble, and Nvidia could face serious competition from China soon. The US economy is flailing, except for AI capex, which is currently larger than consumer spending. And now, these vague investment plans can conjure up huge sums of fictitious capital.

In other words, this deal is bullish for AI on paper, but it could turn fragile at a moment’s notice. Can anything other than AI-to-AI deals keep these firms’ valuations rising? If OpenAI and Nvidia suffer a downturn, could it disrupt the US economy?

For good or ill, the markets are putting all their eggs into the AI basket.