Komag's ( KOMG) third-quarter earnings more than tripled from a year ago on swelling demand for high-capacity hard drives in new personal computers. The San Jose, Calif., company earned $32.0 million, or 97 cents a share, in the quarter, compared with $9.3 million, or 31 cents a share, a year ago. Sales jumped 76% from last year to $180 million. Analysts surveyed by Thomson First Call were forecasting earnings of 94 cents a share on sales of $179.5 million. "A favorable product mix shift to higher sales of advanced 3.5-inch disks at 100-gigabytes and greater, combined with an increase in sales of aluminum substrates, led to a record level revenue of $180.0 million and a 17.8% net margin," the company said. The company forecast fourth-quarter revenue of $183.6 million to $187.2 million and said its net margin should be 17% to 18%. Analysts pegged fourth-quarter revenue at $185.5 million. "Overall demand continues to be very strong entering the traditionally seasonally strong fourth quarter," it said. "Our capacity expansions are currently progressing on schedule. We expect to have a limited amount of incremental capacity from our first expansion in the later part of the fourth quarter of 2005." The stock closed at $27 Wednesday.