According to diskpart, a disk has four partitions:

Partition 1 - Recovery - 11GB
Partition 2 - System - 100MB
Partition 3 - Reserved - 128MB (MSR / OEM Partition)
Partition 4 - Primary - 464 GB

The four volumes are listed as:

Volume 0 - C - Blade - NTFS - Partition - 464 GB - Healthy -
Volume 1 -   - Recovery - NTFS - Partition - 11 GB - Healthy - Hidden
Volume 2 -   - SYSTEM - FAT32 - Partition - 100MB - Healthy - Hidden
Volume 4 - C - Blade - NTFS - Partition - 464 GB - Healthy - Hidden

More details:

• "detail partition" with Partition 3 selected claims that no volume is associated with the partition
• "detail partition" with Partition 4 selected claims that only volume 4 is associated with the partition
  
• "detail volume" with Volume 0 selected displays a list of attributes, plus volume capacity and free space
• "detail volume" with Volume 4 selected displays a single attribute - offline: no
• Removing or setting the drive letter of either Volume 0 or Volume 4 results in the change being mirrored to the other volume.
• The above information was obtained after booting into a Windows PE shell.  Diskpart does not show Volume 4 when running Windows 8.1 from the primary partition.
• Disk Management in W8.1 does show the duplicate volume entry as a Healthy OEM Partition (465 GB). However, it does not indicate the existence of Partition 3 in the disk view.
  

Problems resulting from misconfiguration:

• Disk Manager does not permit management actions on volumes (context menu shows only "help" entry, window menu entries are all disabled)
  
• BitLocker is unable to encrypt the volume, complaining that it is hidden.

Otherwise, the system runs just fine so far.  This is a new 2014 Razer Blade. (Have verified that another new 2014 Razer Blade has the exact same problem, so it's something that Razer misconfigured.  Their support isn't terribly helpful, unfortunately.)

• Edited by tvald 11 hours 6 minutes ago formatting