* July nonfarm payrolls 215,000 vs 223,000 estimate
* Major indexes poised to end the week lower
* Traders pricing a 52 pct chance for Sept hike
* Nvidia hits 4-month high after revenue beats estimates
* Indexes down: Dow 0.62 pct, S&P 0.65 pct, Nasdaq 0.86 pct (Updates to mid-afternoon)
By Noel Randewich
Aug 7 (Reuters) - U.S. stocks dropped on Friday after solid job growth data for July pried the door open a little wider for a potential interest rate hike by the Federal Reserve in September.
Wall Street took the latest signs of an improving economy as a fresh reason to sell shares in a market that has remained range-bound for much of 2015 in anticipation of the Fed's first interest rate hike in nearly ten years.
Nonfarm payrolls increased 215,000 last month, less than the 223,000 forecast by economists, but the unemployment rate held at a seven-year low of 5.3 percent.
U.S. overnight indexed swap rates rose after the latest jobs data, suggesting traders were pricing a 52 percent chance that rates would be raised in September rather than December, up from 47 percent prior to the data, according to John Briggs, head of cross-asset strategy at RBS Securities Inc in Stamford, Connecticut.
"It's enough to keep the Fed on track to raise rates in September, but it's not enough to end the debate," said John Briggs, head of cross asset strategy at RBS Securities in Stamford, Connecticut.
At 2:19 pm, the Dow Jones industrial average was down 0.62 percent at 17,312.21 and the Nasdaq Composite was off 0.86 percent at 5,012.90.
The benchmark S&P 500 dipped 0.65 percent to 2,070.02. After hitting a record high in May, the S&P 500 is now up less than 1 percent for the year.
On Friday, nine of the 10 major S&P sectors were lower, with the energy index's 1.44 percent fall leading the decliners as oil prices headed for a sixth week of losses.
Exxon Mobil's 1.5 percent drop weighed the most on the S&P 500.
Earnings continue to remain in focus. With about three-quarters of the S&P 500 companies having reported second-quarter results, profits are estimated to have increased 1.6 percent, while revenues are projected to have fallen 3.4 percent, according to Thomson Reuters data.
Cablevision Systems' shares fell 5.8 percent after the company managed to stem video subscriber losses, but at the cost of margins.
Nvidia's shares were up nearly 14 percent at $23.25 a day after the chipmaker reported a surprise rise in quarterly revenue.
Decliners outnumbered advancers on the NYSE by 1,895 to 1,108. On the Nasdaq, 1,846 issues fell and 899 advanced.
The S&P 500 index was posting 3 new 52-week highs and 15 new lows; the Nasdaq Composite was recording 24 new highs and 141 new lows. (Additional reporting by Tanya Agrawal; Editing by Bernadette Baum)