Marvell Technology Group ( MRVL) plummeted following the close Monday after the Santa Clara, Calif., chipmaker said third-quarter revenue will be lower than expected. The company also told investors it will restate past financial results due to discrepancies in its past stock-option grants. The company said revenue in its fiscal third quarter will be down about 10% from the $574 million in second-quarter sales. Analysts polled by Thomson Financial were looking for revenue to rise about 1.4% sequentially, to $582.3 million. EPS is projected to be 21 cents. Separately, Marvell said that a special committee of its board of directors looking into past stock-option practices has reached a preliminary conclusion that the actual measurement dates of certain past stock-option grants likely differ from the recorded grant dates for such awards. As a result, Marvell's board has concluded that the company will need to restate previous financial statements to record additional noncash charges for stock-based compensation expenses. Shares were tumbling $2.94, or 15.40%, to $16.15. Navarre ( NAVR) shares advanced after the New Hope, Minn.-based video-game publisher said its Navarre Distribution Services division signed a distribution supply agreement in which it will supply OfficeMax ( OMX) with third-party software titles for its U.S. retail locations. Navarre shares were gaining 11 cents, or 2.72%, to $4.15. Actel ( ACTL) lost ground after the Mountain View, Calif.-based chipmaker said it was reviewing its past stock-option-granting practices. The company said a special committee of Actel's board is leading the effort and has retained independent legal counsel to assist. Actel said it informed the Securities and Exchange Commission about the internal review. Also, the company said that a complaint was filed on Aug. 30, in the U.S. District Court for the Northern District of California, by Frank Brozovich, on behalf of Actel, against certain officers and directors. The derivative legal action relates to certain options grants that were allegedly backdated, the company said. Shares were trading down 21 cents, or 1.4%, to $15.