TYAN M3291 Basic Manual page 59

Compatibility Note: For consistency going forward, this version of the specification
terminates all pull-ups to the +3.3VDC rail whereas earlier versions of the specification
terminated some of these signals to the +5VDC rail. This specification is backward-
compatible with motherboards that are compliant to the earlier termination specification.
Document #: D1739 - 200
59
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