This is why you NEVER use RAID 0. Ever. (I'm not accusing you, but your sysadmin was pretty irresponsible to have used such a dangerous configuration without a rock-solid backup plan.) Your ONLY hope for the current data:   Try the "copy"disk? Best chance for that to work?   Umm ... depends on what exactly the "copy disk" is. Current config is a 2-disk RAID 0, so I'm not exactly sure what a single disk labeled "copy" is going to be. You can try putting it in and saving the disk config and seeing what happens, but it will only work if it is a single-disk RAID 0. I would not hold my breath.
Server has two logical drives A00 and A01. A00 has two physical drives (00, 01) which have the boot partition. They appear as a RAID array in the Perc 4.1 controller (ctrl-M). Logical drive A01 has three physical drives which seem fine. at the bottom of the RAID arrays window there is a drive labeled PROC in slot 6, and there is a physical drive in that position, with a nice green light, but "not responding" (I do not believe it said "ready"). Problem: Drive A00.00 failed with a "Media" error. Server is offline and will not boot. Drive blinks with green and amber lights. Can't boot after pulling the drive A00.00 either. Bigger problem: I lost my Sysadmin, and now several people including myself, want this server back online if possible. Possible something: My former sysadmin left me disk labeled "Copy of 0" for this server. Hoping for the best, I replaced the failed drive with a new drive, but it was immediately marked as failed. I purchased another two new drives. Same thing happened.. marked as a failed drive with a media error. I formatted the new drive with no effect. I have gone into the RAID management Utility (?) and rescanned the drives, hoping it would be recognized as a new drive. It was not. I have done my due diligence online, and found suggestions ranging from just forcing the new drive online, to complex processes of pulling select drives to all the drives, forcing different ones online, or clearing the RAID config, putting the drives back exactly, booting to Perc controller, then looking for the drives to be recognized.  Is anyone willing to help me try and fix this?  This is just slightly beyond my expertise, particularly with older systems. I have not touched the "Copy of 0" and I still have another new drive to work with. The drives actually have some important data... including a full month of recent work. But there's no way the people in charge here will pay for data recovery.
Ancient PE 2600 with failed boot disk