The attorney general of New York, Andrew Cuomo, has launched an antitrust probe into chip giant Intel.
Cuomo is investigating whether Intel coerced customers to exclude its main rival AMD from the worldwide market for x86 computer processing units (CPUs).
"After careful preliminary review, we have determined that questions raised about Intel's potential anticompetitive conduct warrant a full and factual investigation," said Cuomo. "Our investigation is focused on determining whether Intel has improperly used monopoly power to exclude competitors or stifle innovation."
The investigation will focus on whether Intel penalised its customers, primarily computer manufacturers, for purchasing x86 CPUs from competitors; whether it improperly paid customers for exclusivity; and whether it illegally cut off competitors from distribution channels.
The attorney general's office served a "wide-ranging" subpoena seeking documents and information on Intel on Thursday.
Intel is currently under investigation by the European Commission on antitrust charges. The charges were sent as a so-called "statement of objections" to Intel on 26 July, 2007, and the chipmaker formally responded on 7 January.
In July, the Commission's view was that Intel had sought to exclude AMD from the x86 CPU market by providing rebates to original equipment manufacturers (OEMs) on the condition they obtain all or the majority of their CPUs from Intel.
The Commission also maintained that Intel paid OEMs to delay the launch of products containing AMD chips, and that it offered server CPUs to strategic partners at below-average cost in bids against AMD-based products.
Intel is also under investigation by the Korean Fair Trade Commission on anti-competition charges, according to Cuomo's offfice.