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PCI Express is a serial link, which doesn't require parallel delivery, and can send more data down fewer wires. A board with six parallel PCI slots will come with more than 1,000 pins, metallic knobs that connect chips to wires. A similar PCI Express board can be made with fewer than 400 pins, said Mike Fister, senior vice president of Intel's Enterprise Platforms Group, who demonstrated PCI Express on stage last week for the first time at the Intel Developer Forum in San Jose.