By Nathalie Tadena

Dell Inc.'s (DELL) fiscal second-quarter earnings fell 18% as the computer giant recorded weaker revenue, led by declines in its consumer segment.

Shares slid 3.7% to $11.89 after hours Tuesday as revenue missed the company's expectations. Dell also lowered its full-year guidance and offered downbeat revenue guidance for the current quarter.

Dell, one of the world's biggest personal-computer makers, now sees full-year earnings of at least $1.70 a share. It had previously forecast earnings to exceed the $2.13 recorded in fiscal 2012.

Dell forecast third-quarter revenue to decline 2% to 5% from sequentially, which would amount to a range of about $13.76 billion to $14.19 billion. Analysts polled by Thomson Reuters most recently projected revenue of $14.85 billion.

Dell, which in recent years has looked to move beyond its core personal-computer business and broaden its own portfolio of products for corporate customers, faces stiff competition across its business lines. Dell has noted that some consumers were putting off computer purchases and instead focusing their attention on mobile devices.

Faced with soft PC sales, Dell has attempted to boost both revenue and profit by acquiring higher-margin businesses, including data-storage, security and networking technologies. The company has made a number of acquisitions in recent months, unveiling in July plans to buy business-software maker Quest Software Inc. for $2.36 billion.

"Growth in our PC business was challenging, as we saw a tough macroeconomic and competitive environment, and continued to focus on higher-value solutions in this business," said Chief Financial Officer Brian Gladden.

In the latest quarter, Dell's revenue from desktop personal computers declined 8.9%.

For the quarter ended Aug. 3, Dell reported a profit of $732 million, or 42 cents a share, down from $890 million, or 48 cents a share, a year earlier. Excluding acquisition-related charges and other items, per-share earnings fell to 50 cents from 54 cents.

Analysts polled by Thomson Reuters had projected a per-share profit of 45 cents.

Revenue was $14.48 billion, a 7.5% decline from a year earlier and a 0.4% increase from the first quarter.

Dell's downbeat view in May called for revenue to increase 2% to 4% from the first quarter's $14.42 billion.

Gross margin narrowed to 21.6% from 22.5%.

Revenue from the mobility-product category, which includes notebook computers and other mobile devices, declined 19%.

Revenue in the consumer segment sank 22% in the latest period, following a 12% decline in the first quarter.

The public customer segment's revenue slid 6.1% while the large enterprise customer segment's revenue slipped 3%. Revenue from small and medium businesses fell 1.5%.

The stock, which hit its lowest level in about two years earlier this month, has fallen 18% over the past three months, though the close of trading Tuesday.

Write to Nathalie Tadena at nathalie.tadena@dowjones.com

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