* Morgan Stanley's stock soars after strong results
* Shares of eBay, Intel fall after disappointing forecasts
* Bernanke soothes markets again in congressional testimony
* Dow up 0.5 pct, S&P 500 up 0.5 pct, Nasdaq up 0.1 pct
NEW YORK, July 18 (Reuters) - The Dow and the S&P 500 rose to all-time intraday highs on Thursday as Morgan Stanley and others reported better-than-expected earnings and Federal Reserve Chairman Ben Bernanke's comments further reassured markets.
Shares of Morgan Stanley jumped 4.6 percent to $27.76 after the bank posted a 42 percent increase in quarterly profit as stock trading revenue soared. The S&P financial index climbed 1.3 percent.
A rally in the shares of UnitedHealth helped lift the Dow and other health insurers' stocks. UnitedHealth gained 6.6 percent to $70.63 after the company's results beat expectations, while the Morgan Stanley healthcare payor index rose 3 percent.
The news helped both the Dow and the S&P 500 hit new intraday highs shortly after the opening bell. The Dow climbed as high as 15,589.40, while the S&P 500 touched a session high of 1,693.12.
Analysts' estimates for corporate earnings have been lowered so much that investors believe the low targets should be easily exceeded. Instead, investors will likely hone in on revenue figures and outlooks.
"I've been encouraged by the financial sector in general," said Joe Bell, senior equity analyst with Schaeffer's Investment Research, in Cincinnati. "Financials have had a lot of strong positive reactions and reports."
Of the 21 financial companies that have reported quarterly earnings so far, 76 percent have surpassed estimates, Thomson Reuters data showed.
The Dow Jones industrial average was up 78.71 points, or 0.51 percent, at 15,549.23. The Standard & Poor's 500 Index was up 9.09 points, or 0.54 percent, at 1,690.00. The Nasdaq Composite Index was up 3.99 points, or 0.11 percent, at 3,613.99.
With the benchmark S&P 500 up 18.6 percent for the year, investors are watching for any signs of how soon the Federal Reserve will start to wind down the pace of its $85 billion a month in bond purchases. The Fed's stimulus program has helped drive the U.S. stock market's rally this year.
Speaking before the House Financial Services Committee on Wednesday, Bernanke stressed that the timeline for winding down the Fed's stimulus program was not set in stone.
On Thursday, Bernanke delivered the same message to the Senate Banking Committee. He said economic data since the Fed's June meeting has been mixed, adding that "it's way too early to make any judgment" about the impact for the central bank's forecasts.
IBM raised its full-year outlook and reported earnings that beat estimates, though the company missed forecasts on revenue. Shares of International Business Machines rose 1.9 percent to $198.24. IBM gave one of the biggest lifts to the S&P 500 and helped offset losses by Intel and eBay.
Intel, which also limited the Nasdaq gains, slid 3.7 percent at $23.25 after the world's biggest chipmaker cut its full-year revenue forecast, while eBay fell 6.8 percent to $53.47 after it said full-year results would be at the low end of its forecast range.
Analysts expect S&P 500 companies' second-quarter earnings to have grown 3.5 percent from a year earlier, with revenue up 1.1 percent, according to Thomson Reuters data.
A meeting of Dell shareholders to vote on founder Michael Dell's $24.4 billion offer to take the company private was adjourned to next week. Dell's stock rose 1.9 percent to $13.13.
Shares of Google, expected to report earnings after the bell, slipped 0.8 percent at $911.40. Shares of Microsoft , also set to release results after the close, tumbled 1.2 percent to $35.32. Microsoft was among the Nasdaq's most actively traded stocks.