* HP shares slide after 3PAR offer
* Utilities sector leads gains as buyers seek safety
* 3M CEO says may double acquisition spending in 2010
* Dow, S&P 500 flat, Nasdaq down 0.6 pct (Updates to midday, changes byline)
By Rodrigo Campos
NEW YORK, Aug 23 (Reuters) - Falling technology shares weighed on the Nasdaq Composite index on Monday and offset gains by utilities, healthcare and other defensive sectors.
The Dow and the broad S&P 500 index were little changed.
But shortly after the open the indexes rose nearly 1 percent as acquisition deals lifted sentiment. However, a possible bidding war over data storage company 3PAR between Hewlett-Packard Co and Dell Inc sent shares of HP down 2.3 percent, which helped to drag tech stocks down.
"On the one hand, the M&A and all these buyback announcements are supportive and they indicate the market has value," said Nick Kalivas, senior equity index analyst at MF Global in Chicago.
"On the other hand, the economic numbers really are not showing dramatic forward momentum and people aren't willing to pay up for earnings."
Tech shares fell on lingering concerns about the economic recovery and the impact on profits. Recent weak economic data, including reports on employment and manufacturing, added to the cautious tone and depressed trading volume levels.
Both the Dow and S&P have notched two straight weeks of losses after stocks posted their best month in a year in July.
The Dow Jones industrial average dipped 1.90 points, or 0.02 percent, to 10,211.72. The Standard & Poor's 500 dropped 0.16 points, or 0.01 percent, to 1,071.53. The Nasdaq Composite fell 12.20 points, or 0.56 percent, to 2,167.56.
The S&P 500 was kept afloat by gains in utilities and healthcare stocks, traditionally considered defensive plays as they are less sensitive to the economy.
"If you have a dividend and are not as economically sensitive, that's where a lot of people are hiding out," said MF Global's Kalivas.
The S&P utilities sector rose 0.7 percent while the healthcare stocks added 0.6 percent.
HP bid $24 a share in cash for 3PAR, topping an earlier bid from Dell. Shares of 3PAR surged 40.7 percent to $25.38, while HP dropped 2.3 percent lower to $38.95. Dell shares fell 1.5 percent to $11.89.
Dell's announcement was the second major technology deal last week. Intel Corp moved to acquire software maker McAfee Inc for $7.7 billion..
3M Co's Chief Executive George Buckley said the Dow component may spend about $2 billion on acquisitions in 2010, twice its previous estimate. 3M shares gained 0.8 percent to $81.31.
Campbell Soup Co may make a $2.3 billion break-up bid for Britain's United Biscuits, which is owned by private equity firms PAI Partners and Blackstone Group LP, according to a report in London's Sunday Times. Campbell shares were up 0.8 percent to $36.94. (Reporting by Rodrigo Campos; Additional reporting by Leah Schnurr; Editing by Kenneth Barry)