Shares of

SigmaTel

(SGTL)

were among technology's winners Wednesday, vaulting 31% after the chipmaker posted better-than-expected second-quarter results.

The company earned $2.9 million, or 8 cents a share, on revenue of $43.8 million. Excluding a tax benefit and other one-time items, the company recorded a loss of $3.3 million, or 10 cents a share. Analysts polled by Thomson First Call expected a much wider loss of 51 cents a share and revenue of $42 million. A year earlier, the company posted adjusted earnings of $11.1 million, or 30 cents a share, on revenue of $69.6 million.

Separately, SigmaTel announced the sale of its PC audio line to

Integrated Device Technology

(IDTI) - Get Report

for about $80 million. The PC audio business represented about 20% of SigmaTel's overall revenue during the second quarter.

For the third quarter, SigmaTel sees an adjusted loss of 29 cents to 37 cents a share on revenue of $36 million to $42 million. Without taking into account the sale of the PC audio product line, the company would have projected revenue of $42 million to $50 million. Analysts project a loss of 30 cents a share on revenue of $53.6 million. Shares were trading up $1.18 to $5.03.

Manhattan Associates

(MANH) - Get Report

jumped 13% after the supply-chain software maker posted better-than-expected second-quarter results. The company earned $7 million, or 25 cents a share, on revenue of $77.9 million. Analysts expected earnings of 27 cents a share on revenue of $68.7 million. During the year-earlier period, the company recorded adjusted earnings of $7.5 million, or 25 cents a share, on revenue of $61.4 million.

Looking ahead, Manhattan Associates sees third-quarter earnings of 22 cents to 27 cents a share, before certain items. Analysts project earnings of 25 cents a share. Manhattan Associates shares were trading up $2.48 to $21.40.

Trimble Navigation

(TRMB) - Get Report

rose 8% after the global positioning-technology company posted better-than-expected second-quarter results. The company earned $28.5 million, or 49 cents a share, on revenue of $245.3 million. Excluding items, the company earned $34.1 million, or 59 cents a share. Analysts expected earnings of 52 cents a share and revenue of $236.7 million. During the year-earlier quarter, the company posted adjusted earnings of $24.9 million, or 44 cents a share, on revenue of $204.2 million.

Trimble forecast third-quarter adjusted earnings of 44 cents to 47 cents a share, with revenue of $220 million to $225 million. Analysts project earnings of 45 cents a share and revenue of $219.9 million. Trimble shares were trading up $3.52 to $46.52.

Shares of

SiRf Technology

(SIRF)

sank 24% after the maker of chips for GPS systems posted mixed second-quarter results. The company earned $1.7 million, or 3 cents a share. Excluding items, the company earned $11 million, or 20 cents a share, beating analysts' mean estimate by a penny. SiRf's revenue totaled $57.2 million, slightly short of Wall Street's forecast of $57.3 million. During the year-earlier period, the company posted adjusted earnings of $7.4 million, or 14 cents a share, on revenue of $35.4 million. Gross margin in the most recent quarter was 56.3%, up from 55.2% during the first quarter and up slightly from 56% a year ago. Shares were trading down $6.11 to $19.54.

Shares of

Plantronics

(PLT) - Get Report

tumbled 19% after the maker of wireless headsets posted disappointing fiscal first-quarter results and gave a weaker-than-anticipated guidance. For the period ended June 30, the company earned $12.3 million, or 25 cents a share, on revenue of $195.1 million. Excluding items, the company earned $13.6 million, or 28 cents a share. Analysts expected earnings of 31 cents a share on revenue of $198.6 million. A year earlier, the company earned $21.7 million, or 44 cents a share, on revenue of $148.9 million.

For the fiscal second quarter, Plantronics anticipates earnings of 22 cents to 27 cents a share, before items. The company targets revenue of $190 million to $200 million. Analysts project earnings of 36 cents a share and revenue of $209.1 million. Shares were trading down $3.64 to $15.90.

Other heavily traded technology companies included

Sun Microsystems

(SUNW) - Get Report

, up 19 cents to $4.28;

Intel

(INTC) - Get Report

, down 5 cents to $17.49;

Lucent Technologies

(LU)

, unchanged at $2.08;

Microsoft

(MSFT) - Get Report

, up 3 cents to $24.25;

Oracle

(ORCL) - Get Report

, up 5 cents to $14.98;

Cisco Systems

(CSCO) - Get Report

, down 8 cents to $17.99;

Apple Computer

(AAPL) - Get Report

, up $1.59 to $63.52;

RF Micro Devices

(RFMD)

, up 49 cents to $6.45;

Broadcom

(BRCM)

, down 32 cents to $22.68;

Level 3 Communications

(LVLT)

, unchanged at $4;

ATI Technologies

(ATYT)

, up 16 cents to $19.87.