* Oil jumps, energy stocks lead gains on S&P
* IBM tumbles more than 7 pct after margins miss
* Lam Research forecast weighs on chip stocks
* CSX, UAL jump on strong reports, boost Dow Transports
* Indexes up: Dow 0.02 pct, S&P 0.33 pct, Nasdaq 0.34 pct (Changes comment, adds details, updates prices)
By Sruthi Shankar
April 18 (Reuters) - Wall Street edged higher in a volatile morning session on Wednesday as industrial stocks gained on strong results from some marquee companies and a jump in oil prices boosted energy stocks.
The gains were kept in check by technology shares, which were hit by a 7.2 percent slump in IBM after the company's margins missed estimates and by a slump in semiconductor stocks.
Among industrials, CSX Corp jumped 7 percent after the company topped profit estimates. That lifted other railroad stocks and helped power a 1.2 percent jump in the Dow Jones Transport index.
United Airlines gained 5.1 percent and lifted other airline stocks after reporting a better-than-expected quarterly profit, helped by higher fares.
"Even though it's early in the earnings season, what you're seeing is what folks were hoping - it is in line with expectations," said Thomas Martin, senior portfolio manager at GlobAlt Investments in Atlanta.
"The growth rate is coming in slightly higher as companies report above expectations, but it hasn't been super high."
S&P 500 companies are expected to post an 18.6 percent rise in profits in the first quarter, the biggest increase in seven years, according to Thomson Reuters data.
At 11:23 a.m. ET, the Dow Jones Industrial Average was up 0.02 percent, at 24,792.02. The S&P 500 gained 0.33 percent to 2,715.22 and the Nasdaq Composite rose 0.34 percent to 7,306.12.
The CBOE Volatility index was up 0.72 points at 15.99, marking its first gain after closing lower for six days in a row.
Helping the Nasdaq pull back from a dip earlier in the session was a rise in consumer discretionary stocks, such as Amazon's 1.7 percent rise.
Tesla also rose 2.6 percent after a report that the company was aiming to ramp up production of Model 3 cars to reach its goal.
Oil prices jumped about 2 percent, lifted by a reported decline in U.S. crude inventories and the risk of supply disruptions. The energy sector was up 1.6 percent and led the gainers among the 11 major S&P indexes.
Among the decliners were chip stocks after chip equipment maker Lam Research kept its full-year forecast unchanged, which analysts said could imply a slowdown in demand.
Lam Research fell 4.6 percent and was the biggest decliner on the Philadelphia SE Semiconductor index, which fell 0.65 percent.
Advancing issues outnumbered decliners on the NYSE for a 2.13-to-1 ratio, and on the Nasdaq, for a 1.83-to-1 ratio. (Reporting by Sruthi Shankar in Bengaluru; Editing by Shounak Dasgupta)