UPDATE 2-U.S. video games sales fell 7 pct in September-NPD

(Recasts; adds more data, Nintendo quotes, byline)

By Sue Zeidler

LOS ANGELES, Oct 16 (Reuters) - U.S. video games sales fell 7 percent in September from a year earlier, when sales rose sharply with the release of "Halo 3," according to data from research firm NPD on Thursday.

While NPD analyst Anita Frazier called it the first "true" monthly decline for the industry since March 2006, she said U.S. video game sales remained quite strong despite the rocky economy and were poised to achieve $22 billion or more for the year, excluding PC games.

U.S. sales of video game hardware, software and accessories totaled $1.27 billion in September with software sales falling 6 percent and hardware sales down 9 percent, NPD said.

Frazier said it was important to keep in mind that September's 7 percent decline in video games was against a robust September 2007, when games rose 75 percent from the prior September.

"Last year, Halo 3 released in September 2007 and that game had a huge impact on hardware and software sales," she said.

NPD said an apparent drop in January 2008 from a year ago was not a "true decline" because the data compared a four-week month this year with a five-week month in 2007.

On a per-week basis, sales in January 2008 were actually higher than in January 2007, Frazier said.

The Xbox 360 outsold Sony Corp's (6758.T) PlayStation 3 in September in the United States, with 347,200 units versus 232,400 PS3 consoles. Nintendo Co Ltd's (7974.OS) Wii outsold both systems combined, with 687,000 units.

For the handhelds, Nintendo's DS sold 536,800 units versus 238,100 units of Sony's PlayStation Portable.

The top selling game was LucasArts' "Star Wars: The Force Unleashed," which debuted in September, with 610,000 units for the Xbox 360, 325,000 units for the PS3, and 223,000 units for the Wii.

Cammie Dunaway, Nintendo of America's executive vice president of sales and marketing, noted that despite recent price cuts on Xbox, Nintendo's Wii continues to enjoy significant sales with multiple players in households.

Asked if the company will better stock the popular Wiis for the holidays, she said consumers would start to see this product growing into the market during October.

"Even in September, our internal numbers would suggest that Wii volume was about 37 percent higher than it was last year," she said. (Reporting by Sue Zeidler, editing by Richard Chang)