The Intel spokesman declined to comment on Castellano's calculations. But he said Atom was boosting the company's profit.

"Atom sales in netbooks have given us extra growth and revenue we would not have otherwise seen," the spokesman said in an e-mail. "We're seeing very little arbitrage from our Core-brand of processors as many people buy netbooks as companions to their laptops or as a third or forth home PC purchase."

The spokesman continued, "We are comfortable with the margins we make on Atom and more than pleased with the early returns we're seeing from the family."

Jack Gold, an independent mobile and semiconductor analyst, said Castellano's analysis relies on several flawed assumptions.