Stocks in Motion: Red Hat, Gateway, Sonic Innovations

Updated from 1:16 p.m. EDT

Shares of Red Hat(RHAT Quote) fell Tuesday after the Linux software vendor's CFO unexpectedly resigned and despite the company's upside preannouncement.

Kevin Thompson is leaving to spend more time with his family, the company said Monday night. Shares of Red Hat traded down $2.24, or 9.2%, to $22.06 on volume of 38.2 million shares. An effort to calm investor fears by previewing second-quarter earnings failed to stem the selling. Red Hat put quarterly net income at 5 cents a share, a penny better than expectations.

Computer maker Gateway(GTW Quote) moved higher after the company said it expects to report better-than-expected sales in the second quarter. Citing strength in its retail and professional lines, the computer retailer put quarterly revenue at $860 million to $880 million, up from previous guidance of $798 million. Gateway expects to lose between 13 cents and 14 cents a share before a charge in the quarter, roughly in line with estimates. Shares of Gateway traded up 83 cents, or 22.6%, to $4.50 on volume of 13.3 million shares.

Sonic Innovations(SNCI Quote) fell by as much as 40% Tuesday after the maker of digital hearing aids said that it would report weaker-than-expected second-quarter results. The company said changes in the German health care system would significantly reduce sales and lead to quarterly earnings of 2 cents to 4 cents a share, about half of what was expected. Shares of Sonic Innovations traded down $3.51, or 38.3%, to $5.66 on volume of 5.9 million shares.

In addition to Red Hat and Sonic Innovations, Nasdaq volume leaders included Microsoft (MSFT Quote), up 51 cents to $27.41; Cisco (CSCO Quote), up 33 cents to $23.64; Oracle (ORCL Quote), up 17 cents to $11.71; and Intel(INTC Quote), up 44 cents to $28.43.

In addition to Gateway, NYSE volume leaders included Lucent (LU Quote), up 9 cents to $3.50; Motorola (MOT Quote), down 50 cents to $18.45; Nortel (NT Quote), up 14 cents to $4.04; and General Electric(GE Quote), up 24 cents to $31.81.