Updated from 7:58 a.m. EDT

EMC's ( EMC) first-quarter earnings roughly tripled from a year ago on a 35% jump in revenue -- its highest top-line growth in three years, the company reported before the opening bell Thursday.

But top-line guidance for the second quarter barely exceeded expectations and analysts said the tone of a conference call seemed a bit conservative as the discussion turned to outlook for the rest of the year. For example, when asked if he was "comfortable" with consensus estimates of 34 cents for the year, Bill Teuber, EMC's Executive Vice President and CFO, demurred, saying: "We had a good first quarter, and expect a good second quarter, but people might have different perspectives on what the third and fourth quarters will bring."

After making gains in pre-market trading, EMC's stock turned south and recently was off 11 cents, or 0.8%, to $13.09.

"The Street was looking for more leverage; there may not be as much upside for the year," said Cliff Su, who follows the company for Lazard, which has done investment banking for EMC.

The Hopkinton, Mass., storage giant earned $140 million, or 6 cents a share, on revenue of $1.87 billion in the latest quarter, compared with earnings of $35 million, or 2 cents a share, on revenue of $1.38 billion last year. The latest quarter included a charge of 1 cent a share related to an acquisition.

Excluding the charge, analysts surveyed by Thomson First Call were forecasting earnings of 6 cents a share on revenue of $1.83 billion.

"This wasn't a huge surprise," analyst Wendy Abramowitz of Argus Research said of EMC's quarterly results. "What we're seeing this week is that if a company doesn't beat expectations the stock doesn't do much." (Argus does not have a banking relationship with EMC.)

By segment, EMC said systems revenue totaled $895 million in the latest quarter compared with $752 million a year ago; software revenue totaled $484 million compared with $299 million last year; and services revenue totaled $473 million in its latest quarter compared with $306 million a year ago.

The company said "core" revenue, which excludes recent software acquisitions Documentum, Legato and VMware, rose about 21% in the first quarter from a year ago. EMC said combined revenue at Documentum, Legato and VMware rose more than 30% from a year ago, a significant gain since growing software revenue is a key component of the company's strategy.

The weakening dollar added about 6% to the top line.

Looking forward, EMC forecast revenue for the second quarter of between $1.95 billion and $1.98 billion and earnings of 8 cents a share. Analysts surveyed by Thomson First Call had been forecasting earnings of 8 cents a share on revenue of $1.92 billion.

Selling, general and administrative expenses, as a percentage of revenue, should be between 26% to 29% for 2004, compared to 28.6% in the just-completed quarter. Gross margins should exceed 50% for 2004.