Computer chipmaker Intel has been fined a record 1.06 billion euros ($US1.45 billion) by the European Commission for anti-competitive practices.
The EC found that Intel paid manufacturers and a retailer to favour its chips over those of Advanced Micro Devices between 2002 - 2007.
Intel says it will appeal against the verdict.
Chief executive Paul Otellini says the decision ignores the reality of a highly competitive microprocessor market.
Advanced Micro Devices says the decision will shift the power from "an abusive monopolist" to computer makers, retailers and consumers.
The fine dwarfs the 497 million euro fine levied on Microsoft in 2004 for abusing its dominant market position.