Tech stocks were edging higher Tuesday, as investors were cautious approaching Wednesday's Federal Reserve Open Market Committee meeting.

Apple ( AAPL) shares were climbing on heavy volume, as the computer giant reported brisk sales of its latest version of its OS X operating system, Leopard. The company said it had sold two million copies since it went on sale Friday. Shares were gaining $3.01, or 1.6%, to $188.10.

Google ( GOOG) shares also were gaining 2.5%, after the Wall Street Journal reported the Web giant is close to unveiling long-rumored plans to make applications and services available on mobile phones. Shares were adding $16.76 to $695.99. The two Nasdaq 100 components helped buoy the index, which was up 10.07 points to 2213.49.

Kaufmann Brothers initiated coverage of a pair of chipmakers, sending shares of each in different directions. The firm tagged Nvidia ( NVDA) with a buy rating, and the stock responded by climbing $1.51, or 4.5%, to $35.10. Broadcom ( BRCM) shares, however, were falling 2.8% after Kaufmann started the stock with a hold rating. Shares were shedding 94 cents to $32.19.

Sirius Satellite Radio ( SIRI) was falling 6.7% after the company missed Wall Street's third-quarter revenue expectations. The company posted sales of $241.8 million, a gain of 45% from the year-ago period. But analysts polled by Thomson Financial had expected $244.3 million. Sirius reported a loss of $120.1 million, or 8 cents a share, vs. $162.9 million, or 12 cents a share, a year ago. That's in line with analysts' expectations. Shares were falling 24 cents to $3.37.

XM Satellite Radio ( XMSR), which Sirius is seeking regulatory approval to acquire, also was falling on the news. Shareholders for the two companies are expected to meet separately on Nov. 13 to vote on the proposed combination, but federal regulators have not made a decision yet. XM shares were shedding $1.20, or 7.9%, to $13.97.

Nvidia, Broadcom, Sirius and XM are all also Nasdaq 100 components.

Other earnings stragglers in the tech sector posted mixed results late Monday and Tuesday.

Chipmaker Atheros Communications ( ATHR) was jumping 12.6% after beating profit expectations. The company posted $9.7 million in net income, or 16 cents a share, vs. $6.3 million, or 11 cents a share, in the year-ago period. Excluding items, Atheros earned 28 cents a share, vs. analysts' expectation of 26 cents a share. Shares were gaining $3.77 to $33.68.

On the losing side, On Semiconductor ( ONNN) was sliding 14.4% after the chipmaker missed third-quarter profit targets and offered a bleak revenue outlook. The company reported earnings of $63.8 million, or 20 cents a share, including restructuring charges of $2 million, or a penny. That's below the consensus estimate of 22 cents a share. The company sees fourth-quarter sales of between $402.9 million to $411 million, below the Street's $417.7 million target. Shares were shedding $1.76 to $10.43.

Qwest ( Q) shares were dropping 13.4%, after the phone company posted sliding sales and missed third-quarter expectations. The company posted an adjusted profit of 14 cents a share on sales of $3.43 billion, vs. the expectations of analysts polled by Thomson Financial of 15 cents a share on revenue of $3.49 billion. Shares were losing $1.10 to $7.08.