In the latest salvo, AMD this weekin U.S. District Court in Delaware. Here are some key moments in the companies' entwined histories:
1968--Intel is founded by Bob Noyce and Gordon Moore.
1969--AMD is founded by Jerry Sanders along with a team of former Fairchild Semiconductor employees.
Early 1980s--IBM chooses Intel's so-called x86 chip architecture and the DOS software operating system built by Microsoft. To avoid overdependence on Intel as its sole source of chips, IBM demands that Intel finds it a second supplier.
1982--Intel and AMD sign a technology exchange agreement making AMD a second supplier. The deal gives AMD access to Intel's so-called second-generation "286" chip technology.
1984--Intel seeks to go it alone with its third-generation "386" chips using tactics that AMD asserts were part of a "secret plan" to create a PC chip monopoly.
1987--AMD files legal papers to settle the 386 chip dispute.
1991--AMD files an antitrust complaint in Northern California claiming that Intel engaged in unlawful acts designed to secure and maintain a monopoly.
1992--A court rules against Intel and awards AMD $10 million plus a royalty-free license to any Intel patents used in AMD's own 386-style processor.
1995--AMD settles all outstanding legal disputes with Intel in a deal that gives AMD a shared interest in the x86 chip design, which remains to this day the basic architecture of chips used to make personal computers.
1999--Required by the 1995 agreement to develop its own way of implementing x86 designs, AMD creates its own version of the x86, the Athlon chip.
2000--AMDthat Intel is violating European anti-competition laws through "abusive" marketing programs. AMD uses legal means to try to get access to documents produced in another Intel antitrust case, this one filed by Intergraph. The Intergraph case is eventually .
2003--AMD's big technology breakthrough comes when it introduces a 64-bit version of its x86 chips designed to run on Windows, beating Intel, which for the first time has to chase AMD to develop equivalent technology. AMD introduces its Opteron line of chips for powerful computer server machines and its Athlon line for desktops and mobile computers.
2004--Japan's Fair Trade Commission (JFTC) raids Intel offices in Japan searching for documents. Intel cooperates with the investigation but does not agree with the outcome. JFTC officialsby offering rebates to five Japanese PC makers--Fujitsu, Hitachi, NEC, Sony and Toshiba--which agreed not to buy or to limit their purchases of chips made by AMD and Transmeta.
2005--AMD files an antitrust suit against Intel in U.S. District Court in Delaware. The 48-page complaint alleges in detail that Intel has unlawfully maintained its monopoly in the x86 microprocessor market by coercing customers worldwide from dealing with AMD.
Reuters contributed to this report.