At the heart of the QNAP TS-509 Pro stands an Intel Celeron processor running at 1.6GHz. General purpose CPUs are often used in NAS servers, but for the most part they are clocked closer to 1-1.2GHz. QNAP has chosen to use a faster processor since the TS-509 Pro is designed for use in a corporate office environment where several back up operations may need to take place at the same time. The TS-509 Pro also uses a single 1GB DDR2 memory module that can be upgraded if needed, but many NAS servers only come with 256 or 512MB.
Making an appearance in the TS-509 Pro is the dual LAN or WAN and LAN ports that support 802.3 ad-Link aggregation through its two gigabit Ethernet ports. This is a very useful feature in a business environment where multiple computers are pushing and pulling data to the NAS, but a compatible switch must be used to enable this feature.
Of course, the biggest feature of the TS-509 Pro has to do with the number five, the amount of hard drives that the NAS can use in everything from a single disk to RAID 6. Recently QNAP released an official patch that allows the use of Seagate's 1.5TB drive, so it is possible to have up to 7.5TB of space in RAID 0. However, RAID 5 and 6 would be a much better choice for users since you gain redundancy of data. This protection comes at a cost to available disk space, but if a single drive fails in RAID 5 you will not lose data, in RAID 6 you can fail two drives and still retain all of your data.
The TS-509 Pro uses a dedicated Linux installation that is kept on a 128MB NAND flash module. The open source nature of Linux invites end users to make software packages that run on the fast Celeron processor. QNAP has used the power of the Celeron to produce software that goes far beyond just a storage device.
QNAP recently updated the firmware on the TS-509 Pro which added some new features. The biggest check box in that particular update was enabling support for iSCSI. iSCSI target servers are starting to gain momentum in small to medium sized offices and until recently the feature was only found on much more expensive NAS servers.