NEW YORK (CNN/Money) - U.S. stocks tumbled early Friday as a profit warning from tech leader Microsoft overshadowed any positive earnings news from other companies.

At around 9:35 a.m. ET, the Nasdaq composite (down 29.54 to 1394.21, Charts), Dow Jones industrial average (down 74.79 to 8623.08, Charts) and the S&P 500 index (down 7.38 to 907.22, Charts) all declined sharply.

Microsoft (MSFT: down $2.58 to $52.77, Research, Estimates) warned that its fiscal third-quarter and full fiscal year won't meet current estimates. The company also issued a lot of fairly positive news that was mostly overshadowed in the wake of the warning, including: a 2-for-1 stock split, a dividend on common stock equal to 16 cents per share before the split and better-than-expected fiscal second quarter earnings per share on revenue that was lower than expected.

The news overwhelmed positive earnings reports from companies such as IBM (IBM: down $2.89 to $83.16, Research, Estimates), General Electric (GE: down $0.30 to $24.73, Research, Estimates) and Sun Microsystems (SUNW: down $0.30 to $3.40, Research, Estimates), all of whom met or topped estimates, but saw their stocks fall in the early going.

Microsoft's warning sent European markets lower at midday, while Asian-Pacific stocks ended mostly lower Friday, although Tokyo's Nikkei index closed up nearly 1 percent.

Treasury prices rallied, sending the 10-year note yield down to 4.02 percent from 4.08 percent late Thursday. Treasury prices and yields move in opposite directions. The dollar tested new three-year lows against the euro and also fell versus the yen.

Brent oil futures dipped 35 cents to $30.23 a barrel in London. Gold lost 60 cents to $357.50 an ounce.