NEW YORK -- Dell ( DELL), the No. 3 PC maker but once the world's largest, is in buyout talks with private-equity firms, according to Bloomberg, which cited two people with knowledge of the matter. One unidentified source said Dell is in discussions with at least two firms. The sources, however, said the talks are preliminary and could collapse if the private-equity firms are unable to gain financing or work out a future exit strategy. Sterne Agee analyst Shaw Wu wrote Monday in a client note that a potential takeover is possible but low in likelihood, given the financing needed to buy Dell, which currently has a market value of more than $21 billion, and the PC maker's challenging competition. Dell's Salvation May Be Upon UsFacebook ( FB) is holding a major press event at its headquarters Tuesday and there is plenty of speculation about what the social networker will announce. Facebook often saves its big announcements for the company's F8 developer conference, so this marks a departure from the company's usual strategy. TheStreet's Chris Ciaccia suggested that a search engine is one of the more likely choices for a product announcement, as Facebook looks to take market share away from Google ( GOOG), the search leader. There also is speculation that Facebook could announce a deal with Netflix ( NFLX) to carry streaming video services. 5 Things Facebook Could Be Set to Announce at Mystery Media EventJPMorgan Chase ( JPM) was ordered to take steps to correct poor risk management in connection with the multi-billion dollar trading loss it suffered last year. The Office of the Comptroller of the Currency ordered the bank to remedy the breakdown in risk management that led to the "London Whale" trades -- outsized bets in credit derivatives by a London-based group of traders that caused the bank more than $6 billion in losses. The bank was issued cease-and-desist orders, sanctions that require a bank to change its practices. JPMorgan Chase Under Enforcement 'Whale' Watch: ReportLululemon Athletica ( LULU) raised its fiscal fourth-quarter earnings guidance but said revenue growth would slow. Lululemon said Monday it expects quarterly earnings of 74 cents a share; its previous guidance was 71 cents to 73 cents a share. The yoga-wear company said revenue would be at the high end of its original guidance range of $475 million to $480 million. Lululemon said it expects same-store sales for the period ending Feb. 3 to rise in the high single digits, down from growth of 26% in the same period a year earlier. Analysts expects fourth-quarter earnings of 74 cents a share on revenue of $489 million. Homebuilder Lennar ( LEN) is expected by analysts Tuesday to post fourth-quarter earnings of 44 cents a share on revenue of $1.32 billion. RadioShack ( RSH) said Monday that it was ending an agreement with Target ( TGT) to run mobile phone centers in its stores. RadioShack said it has been renegotiating the terms of the deal with Target since October to make it profitable for both companies, but an agreement couldn't be reached and it will end the contract in April. -- Written by Joseph Woelfel >To contact the writer of this article, click here: Joseph Woelfel >To submit a news tip, send an email to: email@example.com.