Intel's German headquarters has been raided today by EU antitrust officials, who carry out inspections in the Central Processing Unit (CPU) and PC sector.

The European Commission confirmed today that officials carried out unannounced inspections at the premises of a manufacturer of Central Processing Units (CPUs) and a number of personal computer (PC) retailers.

Intel said that it cooperates with the authorities.

"The Commission has reason to believe that the companies concerned may have violated EC Treaty rules on restrictive business practices (Article 81) and/or abuse of a dominant market position (Article 82)," the commission said in a statement.

The surprise inspections were the EU's first major move in response to complaints from smaller rival AMD, alleging that Intel pressed major stores to avoid computers using AMD chips.

Intel, the world's biggest chip maker, is already facing formal EU charges of monopoly abuse for below-cost customer rebates and pricing that the EU says undercut AMD and discourage manufacturers from building computers with their chips.

The raids focused on the final link in the supply chain - the stores that select computers to sell directly to consumers. AMD claims a wide range of bullying tactics by Intel shut out all of its rivals.

There is no strict deadline to complete such investigations. Their duration depends on a number of factors, including the complexity of each case, the extent to which the undertakings concerned co-operate and the exercise of the rights of defence.

EU officials also looked at whether Intel had urged Media Markt - Europe's largest consumer electronics retailer - not to sell computers using AMD chips. The chain, which is owned by German retailer Metro AG, has more than 360 stores in Germany, France, Belgium, Austria, Switzerland, Poland, Hungary, the Netherlands, Italy, Spain and Greece.