By Benjamin Pimentel, MarketWatch

SAN FRANCISCO (MarketWatch) -- Amazon.com Inc. shares rose Wednesday as investors focused on the company's operational results, but Research In Motion's stock rally fizzled as the handset maker rolled out a new product and said it was changing its name to BlackBerry.

Amazon's (AMZN) gains remained in the spotlight, as the company's stock was up more than 5% to $273.83. Late Tuesday, the company reported weak sales but surprisingly strong operating income for its fourth quarter.

The sector also got an early lift from RIM (RIMM) , U.S.-listed shares of which rallied ahead of the much-anticipated rollout of BlackBerry 10 at a launch event in New York.

But RIM shares reversed course late morning, falling more than 5% to $14.84 as the company announced that it was changing its name to BlackBerry.

Chip stocks also posted gains, with Broadcom Corp. (BRCM) adding 1.7% to trade at $34.29. Late Tuesday, the chip maker reported a drop in profit and a weak outlook.

In a note, Bernstein Research analyst Stacy Rasgon said, "Yes, it does appear that Apple shortfalls have affected Broadcom. However, we note unexpected strength in Broadcom's wireless business in Q3 and Q4."

He added: "It is quite probable that some of the shortfall could be due to over-shipment of parts in the wake of what appeared to be fairly rapid order cuts. If true, this could be evidence of 'choppiness' in the market driven by customer mix issues, rather than broader slowdowns in the smartphone market."

Meanwhile, Facebook Inc. (FB) shares traded up 1.5% to $31.26. The advance came ahead of the social-networking giant's fourth-quarter financial results due after the closing bell. and

On the downside, shares of Hewlett-Packard Co. (HPQ), Cisco Systems (CSCO) and Oracle Corp. (ORCL) were in the red.

The Nasdaq Composite Index (RIXF) remained near its break-even point, rising just 2 points to 3,155. The Philadelphia Semiconductor Index (SOX) was ahead 0.6%.

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