The RNDU4000 is a diskless Ready NAS Ultra 4 sku that allows users to build the storage capacity they need,  when they need it,  using NETGEAR qualified hard drives (see compatibility list here) & X-RAID2™ automatic volume expansion technology. With X-RAID2,  users can expand their volumes on-the-fly simply by adding new hard drives or replacing lower capacity drives with higher ones. Ready NAS Ultra 4 is NETGEARs newest 4-Bay multimedia desktop storage system with both NAS & i SCSI SAN support. Ultra 4 provides 2X the performance of the current NV+ (over 80 MBps),  X-RAID2 automatic volume expansion,  secure drag-&-drop remote access (Ready NAS Remote),  optional online backup & recovery service (Ready NAS Vault),  & RAID 0/1/5 for data protection. Ready NAS Ultra & Ultra Plus platforms will also include some new software applications from Ti Vo,  Orb™ & Skifta™. The Ready NAS Ultra family is designed for advanced home users (prosumers) who have large digital media libraries (music,  photos,  videos) & require maximum performance in order to run their bleeding-edge applications concurrently. These products are ideal for media enthusiasts looking for a fast,  high-quality yet affordable storage solution to store,  share & protect their equally high-valued media 
- Now runs on x 86 platform using the latest 1.66 G Hz Intel Atom™ single-core processor. 
- The first Ready NAS for Home product family to include i SCSI support. 
- Extreme performance for bleeding-edge prosumers (advanced home users),  with over 80 MBps throughput (Note: Ultra 4 Plus delivers over 90 MBps throughput). ** Best software partnerships in the Industry** 
- First Ti Vo Compatible DVR network archiving & storage device. 
- First Orb™ powered storage with transcoding capabilities. 
- First media shifting storage device with Skifta™ (access multimedia content while youre away on any connected DLNA devices). ** Best software features in the industry** 
- Only self-managing