Product Reviews

Hard disk backup costs less than most entry-level tape drives, has an equally high storage capacity and offers superior performance. And Tandberg's latest RDX QuickStor adds even more reasons to use hard disks.

The RDX solution comprises a 3.25in form factor chassis that accepts sturdy removable cartridges, with compact 2.5in SATA hard disks mounted inside. Costing £160, the kit looks good value, as it includes a 40GB cartridge, but Tandberg also offers 80GB and 120GB versions. An external USB version sells for around £190, although this will be slower than the internal SATA model.

One problem with hard disks is their lack of hot-swap support, as unless you have them connected to a RAID controller you'll need to power down the host system first. Tandberg Data has neatly solved this conundrum, as its RDX Utility loads a small monitoring service and a software update that allows the eject button to work under Windows. When you hit the button, it releases the drive, allowing it to be safely removed and replaced while Windows is running. The only other product we've seen that allows single hard disks to be hot-swapped is StorCase's Data Express DX115, although the drive had to be disabled

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and locked via a software utility first before the caddy could be removed.

For testing, we installed the device on a 3.2GHz Supermicro Pentium D workstation loaded with Windows XP SP2. With the software utility installed, the RDX appears to Windows as a removable media device, and cartridges appear ready for use a few seconds after loading. However, we initially experienced poor performance, which was due to the device not being set correctly for DMA operations. The way round this is to reinstall the utility, after which the RDX worked fine. Eject operations worked perfectly and the RDX uses a motor drive to slide out the cartridge ready for removal. Cartridges can also be ejected directly from Windows Explorer.

Raw performance was up to the quoted speeds. Iometer reported 33MB/sec average throughput for reading from the cartridge and 32.5MB/sec for write operations. Real-world performance wasn't quite as good, though. Copying a 691MB video file to the cartridge and restoring it back to the PC's system disk both took 26 seconds for an average of 27MB/sec.

Using the bundled Backup Exec 10d software, we created a removable Backup-to-Disk folder location and secured a local partition with 8.2GB of data to the RDX, which returned a decent average transfer rate of 20MB/sec. Overall, an impressive turn of speed, which puts it on par with many mid-range tape drives and twice as fast as Quantum's DLT-V4 tape drive.

Surprisingly, there isn't much choice in the removable hard disk market, with the biggest competition being Iomega's REV drive. Although we like the extremely compact and robust REV media, the RDX QuickStor offers a solid alternative, as it's faster, has a higher capacity and is also more cost-effective for high-capacity backup operations.