To add the new drives into RAID 5 array, you need to stick them in the free slots and go into Array Manager and see if they show, if they do, then you can add them to the existing array. If they don't show up as available devices, then you'll need to flash the PERC firmware/drivers and try again (this will need a reboot).
To expand the C: drive you'd have to find a partition tool. The partition tools are devided by different Windows Operating Systems, usually Windows Server OS and Windows non-server OS.
To work on Windows server 2000/2003/2008, you need server partition software like Partition Wizard Server Edition (It is definately Win Server 2000/2003 supported). Here is a tutorial: resize partition with Partition Wizard Server
To work on Windows 2000/XP/Vista, we recommend freeware Partition Wizard Home Edition. Tutorial: how to resize partition with Partition Wizard Home Edition.
A Dell PE2600.
Raid 5 Configuration 4X36GB Drives.
The server drive cage has 2 more empty slots.
There are additional new 36GB hard drives.
The C: partition on the RAID 5 is already running out of space.
When the c: partition is running out of space, there are two ways to free them.
One, to move the pagefile to another drive while deleting temp files on c drive. And if you use backup software that logs to the C: drive that's a good candiate to reinstall to another volume (or at least move where the logging is done).
Two, to add additional drive to the RAID 5 and distribute the free space to c partition. Can we add the additional new drives to the RAID5 array and allocate free space to C:\ partition without data loss? How to accomplish?