The tech-heavy Nasdaq gained 20.65 to 4,169.54, and the Standard & Poor's 500 index inched down 7.36 to finish at 1,487.37.
Semiconductor stocks posted significant gains. The Philadelphia semiconductor index rose 65.87, or about 6 percent, to 1,134.76, led by Micron Technology, which rose $14.19, or 12 percent, to close at $129. Analysts at Robertson Stephens and Banc of America boosted their ratings on the chipmaker.
Advanced Micro Devices and Applied Materials also posted strong gains. AMD rose $6.88, or 11 percent, to $68 after the company said that it expects first-quarter sales to surpass $1 billion.
Applied Materials rose $6.06 to $104.19 on volume of more than 21.8 million shares--more than three times the stock's average daily volume. Analysts at Adams Harkness raised their rating on the maker of chip manufacturing equipment.
The CNET tech index gained 6.41 to close at 3,194.75. Winners edged out losers, with 57 of the 98 stocks in the index rising and 41 falling.
Of the 18 sectors tracked, semiconductor equipment companies posted the sharpest rise, climbing 5 percent. E-tailers were the day's largest losers, falling 2 percent.
Intel closed up $2.88 at $129.88, and Microsoft fell $2.19 to $86.38. The federal judge who issued a damaging ruling in the software giant's antitrust case this week has moved to expedite the judiciary process by releasing his remedies within 60 days.
The initial public offering of Oratec Interventions, a health products company, was the biggest percentage gainer on the Nasdaq Stock Market. The shares jumped $11.63, or 83 percent, to $25.63. Volume topped 4.2 million shares.
Carey International was the Nasdaq's largest loser after the company reported lower earnings than the year-ago quarter. Shares of the chauffeur company fell $7.50, or nearly 47 percent, to $9.56.
AT&T fell $1.63 to $54.88 as competition in the wireless industry heated up with the merger announcement of BellSouth and SBC Communications. BellSouth shares rose 50 cents to $49.38, while SBC rose 31 cents to $46.31.
Seagate Technology, the hard disk maker in the midst of a major makeover, will begin selling storage servers in a move that mirrors recent efforts by competitors. Its shares rose $2.88 to $53.88.
America Online also announced today that it will release an overhauled version of Netscape Communications' Web browser. AOL rose $1 to $63.88 as the company also said it will join Gateway in marketing services to the Internet appliance market. Shares of Gateway rose $3 to $57.06.
Investors will be watching shares of Yahoo tomorrow. The company reported net income excluding special items of $63.3 million, or 10 cents a share, for the three-month period ending March 31. Analysts expected the leading portal company to post earnings of 9 cents per share.
Yahoo shares fell $1.88 today to close at $165.56. The earnings results were issued after the markets closed; in after-hours trading the shares dipped to about $157.