Advanced Micro Devices (AMD) has formally asked dozens of companies in the PC and server industries to turn over documents related to their purchases of microprocessors as part of its legal campaign against Intel, an AMD spokesman said Thursday.

In late June, AMD filed an antitrust lawsuit against Intel, claiming the world's largest chip maker has used its dominance in the processor business to elbow AMD's chips out of prominent companies such as Dell and Gateway. AMD then issued subpoenas to over 30 PC and server companies requiring them to preserve any and all documents related to their purchases of Intel processors over the last several years.

Now, AMD is asking those companies to hand over the documentation so it can begin sorting through what is expected to be a massive pile of information, said Michael Silverman, an AMD spokesman.

The companies have a 30-day window to respond to the latest round of subpoenas, which were filed this week in the US District Court for the District of Delaware, Silverman said.

AMD is claiming that Intel tied the distribution of rebates on processor purchases to assurances that PC and server companies would restrict their dealings with AMD. Intel has denied AMD's charges, saying that AMD's failure to gain market share is its own fault, not Intel's. AMD hopes to begin a jury trial before the end of next year.