Federal regulators appear to be resisting a formal probe of alleged anticompetitive practices of semiconductor giant Intel Corp., despite requests from members of Congress and corporate rivals.

For years, chip maker Advanced Micro Devices Inc. has charged that Intel, the world’s largest semiconductor maker, violates U.S. antitrust laws. One accusation is that Intel gives rebates to computer maker customers on the condition they not buy some AMD products, a charge the Santa Clara, Calif.-based company included in a 2005 lawsuit against Intel.