* Indexes on track for third straight week of gains
* Nasdaq rises after results from Priceline, Nvidia
* Energy shares weak as crude oil declines on supply woes
* Indexes: Dow down 0.1 pct, S&P flat, Nasdaq up 0.2 pct
NEW YORK, May 10 (Reuters) - U.S. stocks open little changed on Friday but remained on track for a third straight week of gains, while a pair of strong corporate earnings helped the Nasdaq register a small advance.
Equities have rallied this week, with the S&P 500 recently undergoing a five-day streak of record closing highs. Investors expect shares to continue trending higher given the Federal Reserve's accommodative monetary environment and encouraging data on the labor market, including jobless claims on Thursday and last week's payroll report.
"We're getting more constructive on the second half of the year as both the market and the economy are picking up," said Terry DuFrene, investment specialist for JP Morgan Private Bank in New Orleans. "While it has caught us by surprise how much markets have come up, and we might see a decline of 5 percent, we don't see any meaningful pullback ahead."
Clothing retailer Gap Inc was the top gainer on the S&P 500, rising 4 percent to $40.37 after reporting strong results.
Nvidia Corp and Priceline.com Inc led the Nasdaq's rise a day after their results. Both companies beat profit expectations, even as Priceline gave a second-quarter outlook that disappointed.
Nvidia jumped 3.5 percent to $14.42 while Priceline rose 3.4 percent to $762.26.
The Dow Jones industrial average was down 12.20 points, or 0.08 percent, at 15,070.42. The Standard & Poor's 500 Index was down 0.05 points, or 0.00 percent, at 1,626.62. The Nasdaq Composite Index was up 7.65 points, or 0.22 percent, at 3,416.82.
For the week, the Dow is up 0.7 percent, the S&P is 0.8 percent higher and the Nasdaq has gained 1.2 percent. It is the third week of gains for all three indexes.
Boeing Co said late Thursday it had succeeded in getting its factories to churn out 787 Dreamliners at a faster pace this week, a change that came sooner than expected and positions the plane maker to possibly deliver more of the high-tech jet than forecast. Shares of the Dow component were flat at $94.71.
Energy shares may face pressure on Friday as crude oil dropped 2.1 percent on signs of rising supply. Cabot Oil & Gas fell 1.4 percent to $66.71 while Hess Corp was down nearly 2 percent to $69.57.
The group, along with other cyclical sectors closely tied to the pace of economic growth, was among the biggest gainers in the recent rally, spurred by an improved global outlook.
JPMorgan's DuFrene said he was advocating that clients rotate into cyclical shares from defensive stocks.
"A lot of them haven't gotten much price movement this year, but that's temporary. They'll pick up later on and be receptive to improving conditions."
Molycorp Inc reported a first-quarter loss that widened from the prior year, though revenue rose sharply, sending shares up 17 percent to $6.56.
Pain Therapeutics Inc plummeted 48 percent to $2.76 after it said that Pfizer Inc, its marketing partner for painkiller Remoxy, was yet to decide on continuing to seek regulatory approval for the drug.
With 89 percent of the S&P 500 having reported, 66.7 percent have topped profit expectations, above the average since 1994 of 63 percent. However, only 46.4 percent have beaten revenue expectations, well under the average since 2002 of 62 percent.
U.S. Federal Reserve Chairman Ben Bernanke said Friday the shadow banking system continued to pose a threat to financial stability, and that bank funding markets might still not be able to cope with a major default.