When you replace the card and fire it up, it may just pick up the configuration automatically, but if not, you will see a message about a mismatch.  You will need to enter CTRL-M for the configuration utility ... go to Configure, View/Add.  If asked to choose between NVRAM and Disk View, choose Disk View, then save on exit, and you should be good.
I have an old PE 1850 with what I believe to be a bad Perc 4/DC card.  Server will not POST with card installed regardless if drives are inserted into the backplane or not.  Even after allowing a long period of time, will not go past the initial RAID scan.  I have located a used Perc 4/DC controller on Amazon but I'm truly hoping to get the server back online when the card arrives.  I know that the RAID configuration is also located on the drives but I need to know the correct procedure to replace the card and maintain my existing RAID configs for my RAID1 boot volume and the RAID5 storage volume. Thanks for any input. Ken
Replace Bad Perc 4/DC in PE 1850