Dell Inc (DELL.O) will be in focus after the computer major forecast disappointing second-quarter revenue as U.S. and European corporate tech spending weakens and consumer personal computer sales continue to shrink.

Dell shares sank more than 11 percent in after hours trade on Wall Street on Tuesday and were down 12 percent in Frankfurt on Wednesday morning (DELL.F).

Lenovo Group Ltd (0992.HK), the world's No.2 PC maker, said on Wednesday that it expects a slowdown in corporate spending in the United States and Europe amid deepening global economic uncertainty.

Ariba Inc (ARBA.O) will also be in the spotlight after top European software company SAP AG (SAPG.DE) said it plans to buy Ariba in a deal valuing the business and commerce network company at $4.3 billion, its latest maneuver against Oracle (ORCL.O) in the fast-growing Internet-based computing market.

Facebook (FB.O) will also be eyed, after sources said that while company officials traveled the country to talk up the company's $16 billion initial public offering, the social networking giant advised analysts for underwriters to reduce revenue and earnings forecasts.

European stocks sank 1.5 percent in morning trade on Wednesday, reversing a two-session recovery rally, while the euro hit a 21-month low against the dollar ahead of an EU meeting later .EU.

The informal summit is expected to discuss growth-boosting measures and the prospect of common euro zone bonds, but investors doubt it will produce a plan to resolve the debt crisis and restore market optimism, especially as Germany strongly opposes the idea of mutualising debt.

The Congressional Budget Office warned on Tuesday a stalemate over how to tackle a series of fiscal deadlines at year's end would likely push the United States economy into recession in the first half of next year.

Wells Fargo & Co (WFC.N) does not employ the same kind of hedging strategy that has triggered a trading loss of at least $2 billion at rival JPMorgan Chase & Co (JPM.N), the bank's chief risk officer said on Tuesday.

Ford Motor Co (F.N) received its second "investment grade" credit rating on Tuesday, allowing the second-largest U.S. automaker to reclaim its Blue Oval insignia and other assets it mortgaged in 2006 to fund its turnaround plan.

U.S. clothing maker Guess Inc (GES.N) reported a quarterly profit that beat market expectations, helped by fewer discounts at its North American retail business and higher sales in Asia, sending its shares up about 6 percent in after-market trade.

PetSmart Inc (PETM.O) posted a better-than-expected quarterly profit and raised its full-year outlook on strong sales across all its product categories, sending its shares up 8 percent in after-market trade.

On the macro front, investors awaited home price index for March, due at 1400 GMT, as well as new home sales for April, also due at 1400 GMT.

U.S. stocks closed mostly flat on Tuesday after volatility late in the session, with weakness in materials and energy shares offsetting strength in financials.

The Dow Jones industrial average .DJI dipped 1.67 points, or 0.01 percent, to 12,502.81 at the close. But the Standard & Poor's 500 Index .SPX was up just 0.64 of a point, or 0.05 percent, to 1,316.63. The Nasdaq Composite Index .IXIC declined 8.13 points, or 0.29 percent, to close at 2,839.08.

(Reporting by Blaise Robinson; Editing by Catherine Evans)

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