PE6300 Hardware deinstalling the power-board

Hello,

I have troubles with the Power for the harddrives / Backplane. The backplane is ok, so it must be the power-board (or whatever is the right name for the board under the motherboard for the power). I want to change this, but I don´t know how to deinstall this board. Have I to do away the motherboard and all, or what? I hope for helping. Maybee there is a description anywhere in the internet or at Dells page.

Thanks for answering

Siegfried"