The European Commission has fined microprocessor-maker Intel more than €1bn (£900m) for violating European antitrust legislation, saying that the chip maker abused its dominant market-position to exclude competitors from the market for x86 central processing units (CPUs).
The commission has also ordered Intel to cease the illegal practices immediately.
The commission found that Intel engaged in two specific forms of illegal practice.
First, Intel gave wholly or partially hidden rebates to computer manufacturers on condition that they bought all, or almost all, of their x86 CPUs from Intel.
Intel also made direct payments to a major retailer on condition it stock only computers with Intel x86 CPUs.
Such rebates and payments effectively prevented customers - and ultimately consumers - from choosing alternative products.
Second, Intel made direct payments to computer manufacturers to halt or delay the launch of specific products containing competitors' x86 CPUs and to limit the sales channels available for those products.
Competition commissioner Neelie Kroes said: 'Intel has harmed millions of European consumers by deliberately acting to keep competitors out of the market for computer chips for many years.
'Such a serious and sustained violation of the EU's antitrust rules cannot be tolerated.'
Paul Otellini, Intel Corporation president and chief executive officer disagreed with the European Commission's decision.
He said: 'We do not believe our practices violated European law.
'The directorate general for competition of the commission ignored or refused to obtain significant evidence that contradicts the assertions in this decision.'