Apple Xserve Intel (Late 2006) DIY Procedure for Power Distribution Board - Manual (Page 4)

Xserve (Late 2006) Power Distribution Board Replacement Instructions 
Power Distribution Board Cable
Locate the power distribution board cable.
Disconnect the power distribution board cable from its connector on the drive interconnect
backplane.
Disconnect the power distribution board cable from the power distribution board and
remove the cable from the Xserve.
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