Shares in computer giant Dell have fallen more than 4% after the US firm delayed the publication of its latest quarterly earnings results.
Dell is facing stiff competition from rival Hewlett-Packard
Dell said the third-quarter figures, which had been scheduled for Thursday, would be published later in the month.
The firm said the delay had been caused by the "level of complexity" in the preparation of its preliminary results.
Rival computer firm Hewlett-Packard is expected to unveil robust quarterly results later on Thursday.
Shares in Dell fell $1.09 to $24.66 in early trading on the Nasdaq exchange.
Dell said the delay of its earnings report was unrelated to a current probe being carried out by the US Securities and Exchange Commission (SEC).
The company said market regulators had asked for information "relating to revenue recognition and other accounting and financial reporting matters for certain past fiscal years".
Dell recently lost its place as the world's top ranking firm for personal computer shipments to HP, according to market research firms Gartner and IDC.
"The implication is that this (SEC) investigation is turning out to be more serious than what Dell anticipated," said analyst Shaw Wu, of American Technology Research.