SAN FRANCISCO (Reuters) – Dell Inc&&9;s (DELL.O) quarterly profit plunged 54 percent and its revenue missed Wall Street expectations as sales to large business continued to struggle, driving its shares down 6 percent.

The weak results from the world&&9;s third-largest maker of personal computers surprised analysts since they came after larger rival Hewlett-Packard Co (HPQ.N) had reported stronger-than-expected preliminary earnings.

"It was universally expected they would beat because pretty much everyone else in the PC space has posted strong numbers," Kaufman Bros. analyst Shaw Wu said of Dell. "So, the conclusion is that they lost share -- lost a lot of share."

Dell reported a net profit of &&6;337 million, or 17 cents a share, for its fiscal third quarter ended October 30, down from &&6;727 million, or 37 cents a share, in the year-ago period.

Excluding restructuring and amortization charges, profit per share was 23 cents. Analysts were expecting earnings per share of 28 cents, excluding items, according to Thomson Reuters I/B/E/S, but it was not immediately clear if that was directly comparable quick payday loans.

Dell said revenue fell 15 percent to &&6;12.9 billion, missing the average analyst estimate of &&6;13.2 billion.

The company did not provide a formal outlook for the critical holiday-season quarter, though it said it expects revenue to improve from the third quarter, with its consumer business showing seasonal improvement.

"We are seeing improvement in overall underlying IT demand that is continuing into the fourth quarter," Chief Executive Michael Dell said in a statement.

Shares of Round Rock, Texas-based Dell fell to &&6;14.95 in extended trading, after closing at &&6;15.87 on Nasdaq.

(Reporting by Gabriel Madway and Ian Sherr; Writing by Tiffany Wu; Editing by Richard Chang)

Dell results below Street view, shares fall