* North Korean attack rattles global markets, lifts dollar
* U.S. economy grows faster than previously estimated
* Hewlett-Packard rises premarket after raising outlook
* Futures off: Dow 101 pts, S&P 13.4 pts, Nasdaq 19.5 pts (Updates with GDP data, adds quote)
By Ryan Vlastelica
NEW YORK, Nov 23 (Reuters) - U.S. stock index futures pointed to a drop of nearly 1 percent at the open on Tuesday as rising tensions on the Korean peninsula added to worries about global economic conditions.
North Korea fired dozens of artillery shells on Tuesday, killing two soldiers and setting houses ablaze and South Korea returned fire. The iShares MSCI South Korea Index Fund fell 5.5 percent.
Global stock markets declined while the dollar climbed as the geopolitical tensions and worries over Ireland's debt problems drove investors to the relative safety of the U.S. currency. Crude oil futures sank 1.6 percent.
"We were already in a negative point of view, and this is pushing people over the edge," said Jeffrey Friedman, senior market strategist at Lind-Waldock in Chicago. "With all the issues going on in Europe already, this is just another thing on the negative side of the ledger."
In the latest economic data, the U.S. economy grew faster than previously estimated in the third quarter, the government said, but still not enough to address stubbornly high unemployment.
S&P 500 futures fell 13.4 points and were below fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures dropped 101 points, and Nasdaq 100 futures lost 19.5 points.
Dow component Hewlett-Packard Co rose 2.1 percent to $44.15 in premarket trading a day after it raised its 2011 outlook and posted stronger-than-expected quarterly profit.
Irish Prime Minister Brian Cowen challenged the opposition to approve an austerity budget and trigger an EU/IMF bailout before early elections, but Irish media reported Cowen may face calls to resign immediately or turn over his party leadership at a meeting later Tuesday.
European stocks fell nearly 1 percent to a 3-week low, led by falling banking shares. U.S.-listed shares of Bank of Ireland sank 25 percent to $1.67, while HSBC Holding fell 1.7 percent to $51.38.
Among South Korean companies, steelmaker Posco sank 5.1 percent to $95.90 in light premarket action.
Hormel Foods Corp reported higher-than-expected profit on strong sales, while Campbell Soup Co posted lower earnings.
October existing home sales data are scheduled for release later in the morning, while minutes of the Federal Reserve's Nov. 3 Open Market Committee meeting that included its decision for more quantitative easing will be released at 2 p.m. EST (1900 GMT).
Bank shares weighed on Wall Street on Monday as Europe's debt crisis and fears of an insider trading probe sapped buying interest for most of the session.