Nvidia Corp (NVDA.O) forecast fiscal 2013 sales well ahead of market expectations, helped by demand for its graphics chips, sending its shares up 6 percent in extended trade.

Nvidia, whose name is well known to gamers, graphic designers and other high-end users, said it expects 2013 sales of $4.7-$5.0 billion.

We see growth across our entire graphics processing unit (GPU) and mobile-processor business, Chief Executive Jen-Hsun Huang said in a statement.

Analysts, on an average, were looking for sales of $4.45 billion, according to Thomson Reuters I/B/E/S.

For 2013, the company, which has stepped up its push into the mobile devices market, forecast gross margin of about 51-53 percent.

Shares of Santa Clara, California-based Nvidia shares were up 6.2 percent, or 82 cents, at $14 in extended trade. They closed at $13.18 on Tuesday on Nasdaq.