What do you mean by "rebuild a dell power edge 2650 raid controler"? Are you trying to rebuild the controller or the array? Or, are you trying to get the controller seen by the system?
Rebuilding the array should be simple. If you had a drive fail, remove the drive and replace with a new drive.
If you are trying to get the controller seen by the system then you will need a driver for the controller.
As for getting it to "work in a different raid", this sounds like you want to change your RAID configuration. To do this access the bios of the card, delete the current raid array and create a new one. However, you should be aware that deleting the current array will result in a loss of ALL data on the drives.