The European Commission (EC) has upped the ante in its PR war against Intel by publishing a non-confidential version of its ruling alleging that the x86 chip giant broke EC Treaty antitrust rules and abused its dominant position in the market.

The move came in response to Intel’s accusation that the Commission’s decision against it was flawed and that it lacked the evidence to prove that the processor manufacturer had attempted to drive arch-rival AMD from the market by engaging in unfair practices.

But the EC has now outlined two kinds of illegal activity that it claims Intel engaged in – conditional rebates and so-called naked restrictions – and how it sought to conceal its actions as it began recognising the rising threat posed by AMD. This threat became apparent when it realised that customers were actively considering whether to switch vendors, the EC decision said.

The Commission claimed that Intel provided the conditional rebates to computer manufacturers ranging from HP and Dell to Lenovo between October 2002 and December 2007. They were also given to Europe’s largest PC retailer, Media Saturn Holding, between October 2002 and December 2007, the EC alleged.

An example of such activity was noted in an internal presentation at Dell dated February 2003. It was suggested that if the PC maker switched any part of its CPU supplies from Intel to AMD, Intel’s retaliation “could be severe and prolonged with impact to all LOBs [Lines of Business]”.

Naked restrictions, meanwhile, refer to measures aimed at preventing or delaying the launch of computers that are based on competing products. The Commission claimed that it had uncovered such activity in the period between November 2004 and May 2005 in relation to the same three computer manufacturers.

But such actions, it alleged, “harmed consumers throughout the EEA".

"By undermining its competitors’ ability to compete on the merits of their products, Intel’s actions undermined competition, reduced consumer choice and hindered innovation," said the Commission.