Milpitas, California-based Komag Inc warns that it expects its Dastek thin-film head joint venture with Asahi Glass America Inc to report a third quarter loss greater than the $6.3m loss for the second quarter: it said the expected loss reflects slow manufacturing start-ups at Dastek for at least the September and December quarters but increased profits in its media operations for the third quarter to September 28 will largely offset the higher-than-expected loss at Dastek, enabling it to show some growth on quarter-by-quarter basis.