UPDATED: Michael Dell is taking back his troubled company.

Dell's founder and chairman took back the CEO role today, with Kevin Rollins resigning after a tumultuous period in which the company posted lackluster sales and failed to file earnings for consecutive quarters.

The computing systems maker also said in a statement that it expects its fourth-quarter fiscal year 2007 results to be "below the average of First Call estimates for both revenue and earnings per share," dealing another blow to the reeling company.

Dell will retain the chairman role, seeking to right the ship and propel the computer systems vendor into what he calls Dell 2.0, in which the company plans to adapt its computers, servers and other devices to the changes fostered by Web 2.0 applications, such as wikis, mashups and blogs.

Dell spokesperson Dwayne Cox told internetnews.com that the move was a resignation, not an ouster, noting that the company feels this is the right thing to do to move forward.

Though hardly surprising, the move is a certain about-face, coming after Dell defended Rollins' performance and ability as CEO, and repeatedly denied that he would replace him even as shareholders called for that action.

At an event in New York last September, Dell said he disagreed with press and analyst comments that Rollins isn't the right man to lead Dell. He even called Rollins an "excellent executive." On the possibility Dell would replace Rollins, he said: "It's not going to happen."

Cox refused to comment on the events that led to the change at the top, but the investigations into the company's finances, which led to the delay of Dell's second and third-quarter earnings reports, along with indications of weak sales, triggered the action.

Six weeks ago, Dell said it would again delay filing third-quarter earnings results due to the ongoing investigations into its finances.

Those investigations, by the Securities and Exchange Commission (SEC), the U.S. Attorney for the Southern District of New York and Dell's audit committee, concern the possibility of financial misstatements.

In conjunction with the delay, the computer maker also acknowledged that it received a notice of possible delisting from the Nasdaq stock market for failure to report Q3 earnings.

The warning came three months to the day after Dell received a delisting warning from the market for failure to report Q2 earnings, which it still has yet to do.

And reports of batteries exploding in Dell laptops last summer did not help matters.

"Dell has tremendous opportunities ahead of it," said Dell in a statement. "I am enthusiastic about Dell 2.0, which includes our plan to provide the best customer experience, build a strong global services business and ensure our products deliver the best long-term customer value."

"The Board believes that Michael's vision and leadership are critical to building Dell's leadership in the technology industry for the long term," said Samuel A. Nunn, presiding director of Dell's board.

Shares of Dell had jumped by about 5 percent to $25.21 in after-hours trading.