Dell Inc. (DELL.O) on Wednesday delayed its earnings report as the U.S. Securities and Exchange Commission stepped up a probe into the computer maker's accounting, and its shares fell nearly 3 percent.

Dell said the delay of the earnings report, originally scheduled for Thursday, was not related to the SEC's decision to elevate its investigation to formal from informal status.

But the postponement reflects "the level of complexity the company is facing in the preparation of its preliminary results," related to the SEC investigation and its own inquiry into accounting and financial reporting matters, Dell said.

Dell plans to announce preliminary fiscal third-quarter results in a news release "by the end of this month," but will not hold a conference call for analysts as it has in the past.

"The implication is that this (SEC) investigation is turning out to be more serious than what Dell anticipated and what the Street anticipated," said analyst Shaw Wu of American Technology Research, who has a "neutral" rating on the shares.

Dell has disclosed few details about the accounting issues under review, saying only the SEC had asked for information "relating to revenue recognition and other accounting and financial reporting matters for certain past fiscal years."

The company was notified "recently" that the SEC had stepped up its investigation, which it started on an informal basis in August 2005, Dell spokesman Jess Blackburn said.

Dell said in August that while responding to informal SEC inquiries, it came across matters that required a separate review by its board's audit committee. The company, led by Chief Executive Kevin Rollins, later canceled an investor meeting in New York and said it did not know if the accounting reviews would have a material impact on its finances.

Dell had said in August it did not believe the accounting issues would have a material impact.

Round Rock, Texas-based Dell is also facing an inquiry by the U.S. Justice Department into its accounting. The U.S. Attorney's office for the Southern District of New York subpoenaed documents related to its financial reporting from 2002 to the present, Dell said in an SEC filing in September.

The SEC and Justice Department investigations indicated the "possibility of misstatements" in past financial reports, including "issues relating to accruals, reserves and other balance sheet items," that may affect previous results, Dell said in the September filing.

Dell has not yet filed second-quarter results with the SEC, pending the company's internal accounting review.

Dell said on Wednesday it hopes to regain compliance with SEC filing requirements "as soon as possible."

The earnings report delay is just the latest blow for once-high-flying Dell, which last month lost its standing as the world's largest personal computer maker to Hewlett-Packard Inc. (HPQ.N), according to market researcher Gartner Inc.

HP is stronger than Dell in the fast-growing markets of consumer PCs, notebook computers and printers, according to analysts. Most of Dell's business is in corporate computers.

Founded in 1984 by Michael Dell in his University of Texas dorm room, Dell has been struggling with slowing growth, the accounting investigations and a recall of Sony Corp. (6758.T) battery cells in its laptops after several overheated.

Analysts, on average, had expected the company on Thursday to say revenue rose 4 percent to $14.5 billion, the slowest growth in nearly four years, according to Reuters Estimates.

Dell shares fell 2.8 percent to $25.04 in extended trading after closing at $25.75 in regular-session trading on Nasdaq.