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AMD-751™ System Controller Revision Guide

22564B-1—February 2000

Preliminary Information

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Incomplete AMD Athlon System Bus Disconnect Causes AMD-751 To

Hang

Products Affected. C3, C5

Description. An incomplete AMD Athlon™ system bus disconnect sequence (from the AMD Athlon

processor) can hang the AMD-751 system controller. The AMD Athlon may not complete a disconnect

sequence when using STPCLK-throttling power management.

Potential Effect on System. This problem can occur with ACPI thermal zone support (thermal-throttling

power management) or processor C2/C3 support enabled.

Suggested Workaround. STPCLK throttling (thermal zone) and processor C2/C3 are not supported at this

time. STPCLK throttling is not required for support of the ACPI S1 state.

Resolution Status. Fixed in C3.