NEW YORK (CNN/Money) - U.S. stock futures surged Wednesday morning following the surprise announcement that Hewlett-Packard Chairman and CEO Carly Fiorina had stepped down.

About 8:25 a.m. ET, Nasdaq-100 and S&P futures indicated a positive start on Wall Street. Stock futures had been flat prior to the Hewlett-Packard news.

Hewlett Packard (Research) said Fiorina is leaving the company, effective immediately, after being forced out by its board. The company named Chief Financial Officer Robert Wayman as interim CEO.

"While I regret the board and I have differences about how to execute HP's strategy, I respect their decision," said a statement from Fiorina released by the company.

The news buoyed HP's stock more than 10 percent in pre-market trading.

"Hewlett's news will certainly help HP's stock, the technology sector and the overall market," said Timothy Ghriskey, stock market strategist and president of Ghriskey Capital Partners. "There's been speculation that it could also be the prelude to the breakup of the company into two or more pieces."

In other technology-related news, shares of another tech bellwether, Cisco Systems, could experience turbulence when trading gets underway after the company reported disappointing results and guidance late Monday.

Tuesday's after-hours report from Cisco (Research) hit earnings growth targets, but investors have become accustomed to Cisco beating, not meeting, estimates. And the company predicted lower sales in the current quarter. Shares of Cisco fell about 3 percent in heavy European trading early Wednesday.

Early Wednesday, a car bomb outside a convention center in Madrid injured at least 42 people. Spanish King Juan Carlos and Queen Sofia had been set to appear at the center later in the day. Spain's Interior Ministry blamed the attack on a group seeking independence for the Basque region of Spain.

Japan's Nikkei closed slightly lower, with most other major markets in Asia closed due to the lunar new year holiday. Major European markets were lower in early trading.

U.S. stocks closed little changed in Tuesday trading ahead of the Cisco report.

Oil prices continued to fall in early trading Wednesday ahead of a report on U.S. fuel inventories due later in the morning. The March light crude contract lost 32 cents to $45.08 a barrel in electronic trading, while Brent crude fell 14 cents to $42.93.

Treasury prices were slightly lower, raising the yield on the 10-year note to 4.02 percent from 4.01 late Tuesday. The dollar slipped slightly against the euro and yen.

The only economic report due Wednesday is a reading on wholesale inventories in December. Economists surveyed by Briefing.com forecast inventories rose by 0.9 percent, after a 1.1 percent gain in November.

In corporate news, American International Group (Research) reported improved earnings that beat forecasts as the Dow component weathered serious storm losses in the fourth quarter. Meanwhile, Prudential Financial (Research), the nation's No. 2 life insurer, reported that its earnings fell by 34 percent, missing forecasts.

Doughnut retailer Krispy Kreme (Research) announced it is slashing 25 percent of its staff outside of its stores, or 125 to 130 employees, and said it needs to find new funding by the end of March. Shares of the embattled company fell 5 percent in after-hours trading to a near record low.

The Wall Street Journal reported Wednesday that some key shareholders of long-distance provider MCI (Research) were skeptical with talks of a purchase of the company by Baby Bell Qwest (Research) because the offer would apparently hold little premium for current market prices for MCI shares. Some of those key shareholders would prefer that another Baby Bell, Verizon Communications (Research), emerge as a bidder for MCI.

At 1 p.m. ET, executives from Internet search engine Google (Research) are set to hold their first analyst meeting since its initial public offering last August. The company has seen its stock price more than double since its IPO.