By Aditya Soni, Yuvraj Malik and Anna Tong

(Reuters) -Microsoft said it would spend more money this fiscal year to build out AI infrastructure even as growth slowed in its cloud business, another sign the payoff from hefty investments in the technology may take longer than Wall Street had hoped.

Shares fell 7% on the spending forecast but pared losses to trade down 4% after the bell on Tuesday after Microsoft said on a post-earnings call that Azure cloud growth would accelerate in the second half of fiscal 2025.

Big technology companies have been pouring billions of dollars into data centers to capitalize on the generative AI boom. Google-parent Alphabet warned last week that its capital spending would stay elevated for the rest of the year.

Microsoft said its capital spending rose 77.6% to $19 billion in its fiscal fourth quarter that ends June 30, with cloud and AI-related spending accounting for nearly all of the expenditures. For all of fiscal 2024, capital spending totaled $55.7 billion.

Group CFO Amy Hood said the spending was necessary to support demand for AI services and the company was investing in assets that “will be monetized over 15 years and beyond.”

Still, investors who have run up Microsoft stock by nearly a quarter in the past 12 months on AI optimism were disappointed with the Azure growth.

Microsoft predicted that the business would grow 28% to 29% on a constant currency basis in the July-September quarter, compared with estimates of 29.7%, according to Visible Alpha.

That followed a 29% rise in the quarter ended June 30, which was below estimates of 30.6% and marked a slowdown from the previous three months.

“The street doesn’t have a lot of patience. They see you spending billions of dollars and they want to see a pickup in revenue of that amount,” said Daniel Morgan, senior portfolio manager at Synovus Trust, which holds shares in Microsoft.

“If these companies do not hit it out of the ballpark and are far better than the estimates then they are going to be knocked back,” he added.

While overall Azure growth slowed, AI services accounted for a larger portion of the increase in revenue in the June quarter at 8 percentage points, compared with 7 percentage points in the previous quarter.

The company does not break out the absolute revenue figure for Azure, the part of its business best situated to capitalize on booming interest in AI.

CEO Satya Nadella said that Azure AI was now used by more than 60,000 customers, up nearly 60% year-on-year and that the average spend per customer continues to grow.

Nadella has pushed the company to go all-in on the technology, weaving AI into almost every product from search engine Bing to productivity software such as Word.

Large parts of those efforts have been fueled by technology from OpenAI, in which Microsoft has invested about $13 billion, including the 365 Copilot assistant for enterprises.

The productivity business – home to the Office suite of apps, LinkedIn and 365 Copilot – posted growth of 11%, compared with expectations of 10%.

Revenue from its Intelligent Cloud unit – home to the Azure cloud-computing platform – rose 19% to $28.5 billion in the fourth quarter, missing analysts’ estimates of $28.68 billion, LSEG data showed.

Microsoft – seen as a bellwether for the tech industry thanks to its wide-spanning business – said total revenue rose 15% to $64.7 billion in the fourth quarter. Analysts had expected $64.39 billion, according to LSEG data.

Revenue from its personal computing business, which includes Windows and devices such as the Xbox and Surface computers, grew 14% as Microsoft benefited from stabilizing personal computer sales. The PC market grew for the second straight quarter in the April-June period, according to research firm IDC.

(Reporting by Aditya Soni and Yuvraj Malik in Bengaluru and Anna Tong in San FranciscoEditing by Sriraj Kalluvila, Sayantani Ghosh, Matthew Lewis and Sam Holmes)

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