"It was a wait-and-see day," said Todd Clark, head of listed trading at WR Hambrecht. "People want to see how the Microsoft case ruling goes," he said.
Clark also said he believes that investors are adjusting to last week's rally. The markets have seen a "sideways sort of tape since they are still digesting the healthy gains from last week," Clark said.
The Nasdaq composite index rose 82.89 to 3,839.26, and the Standard & Poor's 500 index climbed 13.52 to 1,471.36.
The Dow Jones industrial average rose 77.29 to close at 10,812.86 led by IBM and Hewlett-Packard.
At the end of regular trading, Intel closed down 63 cents at $128.94. Microsoft rose 88 cents to $70.50.
As expected, U.S. District Judge Thomas Penfield Jackson issued the ruling today in the Microsoft case, ordering that the software giant be broken into two companies.
The CNET tech index gained 60.06 to close at 2,836.68. Winners edged out losers, with 73 of the 98 stocks in the index rising, 23 falling and two remaining unchanged.
Of the 18 sectors tracked, Internet services, computer memory storage and server hardware companies posted the biggest jumps, rising about 5 percent each. Computer distributors were the day's largest losers, falling 1 percent.
Shares of Applied Micro Circuits, a maker of chips for optical networks, zoomed across many trading desks today. The stock fell $9.94, or 9 percent, to $96.88 on a volume of 25.4 million, more than 6 times the stock's average daily volume, making it the third most active stock on the Nasdaq behind Microsoft and Cisco Systems.
The company disclosed to analysts that sales to Nortel Networks, its main customer, would rise at a lower-than-expected rate in its first fiscal quarter.
Among members of the CNET Tech Index, online trading companies posted strong gains.
E*Trade rose $2.38, or 14 percent, to $19.25. Donaldson, Lufkin, & Jenrette launched coverage on the stock with a "top pick" rating.
Knight Trading Group posted strong gains and rose $2.13, or 7 percent, to $32.38. DLJ also started coverage on the stock with a "buy" rating.
Shares of MicroStrategy and VeriSign made big leaps. MicroStrategy rose $9.63, or 34 percent, to $37.63 on a volume of 16.7 million shares, more than 7 times the stock's average, and VeriSign climbed $19.78, or about 12 percent, to $190.81.
The Philadelphia semiconductor index rose 17.42 to 1,129.60, led by chip designer Rambus, which rose $11.50 to close at $213.50.
Shares of MP3.com made the rounds today. The stock jumped $5.25, or 45 percent, to $16.88 on a volume of 5.07 million shares, more than 4 times the stock's average. Reports out today said the five largest record labels are close to settling their copyright infringement suit against the company and will allow the music site to include the labels' songs on its controversial service.
The New York Stock Exchange and seven other exchanges in Europe and Asia are now in talks to form a stock market that would be open 24 hours a day.