The number of winners trounced losers, with 76 of the 100 stocks in the index rising, 22 declining and two remaining unchanged.
All 18 of the sectors CNET tracks posted gains. Internet content companies posted the sharpest gain, rising 6.6 percent, followed by the CAD/CAM sector, which rose 5.5 percent.
In the broader markets, the Nasdaq gained 149.60 to close at a record high of 5,046.86; the Standard & Poor's 500 added 35.06 to 1,401.76. The Dow Jones industrial average rose 154.17 to 10,010.70, led by Hewlett-Packard, which rose $11 to $151.88.
Intel closed up $3.44 at $118.38, and Microsoft gained $4.44 to $100.00.
The initial public offering of Ireland's Riverdeep Group, an educational software company, was the biggest percentage gainer on the Nasdaq. The shares jumped $46.86, or 234 percent, to $66.86. Volume topped 3.6 million shares.
Among members of the CNET Tech Index, VeriSign and DoubleClick posted strong gains.
VeriSign rose $37.75 to $240.75. The company's stock fell two days ago after it announced it would buy Network Solutions for $21 billion.
DoubleClick rose $11 to $116.75. The company recently announced it would hold off on its marketing plans, which raised privacy issues with Internet users.
VoiceStream Wireless ranked as the biggest loser in the CNET Tech Index, falling $12.38 to $126 on a volume of 3.3 million shares.
The Philadelphia Semiconductor Index rose 48.04, or 3.9 percent, to 1,290.21 as chipmaker LSI Logic gained $8.63 to close at $83.13.