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Backside Bus

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Last Updated May 24, 2021 7:35 am

A microprocessor bus that connects the CPU to a Level 2 cache. Typically, a backside bus runs at a faster clock speed than the frontside bus that connects the CPU to main memory. For example, the Pentium Pro microprocessor actually consists of two chips — one contains the CPU and the primary cache, and the second contains the secondary cache. A backside bus connects the two chips at the same clock rate as the CPU itself (at least 200 MHz). In contrast, the frontside bus runs at only a fraction of the CPU clock speed.