Nasdaq 100 Leaders and Laggards: Nvidia, Amylin

The index, which includes 100 of the largest nonfinancial securities listed on the Nasdaq Stock Market, fell 7.17 points to 1,972.54. The broader Nasdaq composite fell 10.52 points to 2,448.94.

Shares of Nvidia declined $1.41, or 5.9 percent, to $22.28, after an analyst downgraded the stock.

Personal navigation device maker Garmin declined $2.79, or 5.6 percent, to $46.80. Lehman Brothers analyst Jeffrey Kvaal said the introduction of Apple's latest iPhone could provide new competition for Garmin ahead of its own handset launch.

Virgin Media slipped 88 cents, or 5.5 percent, to $15.12.

On the rising side, shares of Amylin Pharmaceuticals Inc. added 90 cents, or 3.4 percent, to $27.74, following positive study data on its long-acting version of diabetes drug Byetta.

Apollo Group Inc., which operates the University of Phoenix, gained $1.40, or 3.1 percent, to $47.86.

Shares of Hologic Inc. rose 60 cents, or 2.6 percent, to $23.79. Late Monday, the developer of medical diagnostics technology said it will buy Third Wave Technologies Inc. for $580 million.