Tandberg 220LTO/420LTO Drives
We tested two LTO tape drives from Tandberg: the internal 420LTO (an LTO-2 drive), and the external 220LTO (an LTO-1 drive); note that both drives are available as internal or external models. The drives are heavy and have a sturdy feel to them, and definitely left the impression that they are robust, which is further evidenced by Tandberg's three-year warranty. First, let's have a look at Tandberg's 420LTO, its internal LTO-2 standard drive.
Tandberg 420LTO: 200 GB, Internal
With LTO being an open standard, some drive manufacturers try to differentiate their products by specializing in certain features. Tandberg has concentrated on low power and small dimensions in its 420LTO drives. With an advertised 18 W operating power consumption, the 420LTO needs no fan, and it fits into a standard half-height 5.25" drive bay.
Those reading the marketing materials may be a bit confused by the advertised specifications of 400 GB capacity and 48 MB/s transfer speed. Pay close attention to those asterisks, however, because these advertised speeds assume a 2:1 hardware data compression ratio. The inline hardware compression is part of the drive (more on that later), but this means native uncompressed specifications of 200 GB capacity and 24 MB/s transfer can be expected from the unit. That 24 MB/s is shy of the LTO-2 standard's 40 MB/s transfer rate, so maybe that's where Tandberg made the tradeoff to get the drive to work with low power, low heat, and small size.
Tandberg 220LTO: 100 GB, External
The second drive we tested was Tandberg's external version of their 220LTO, a LTO-1 standard drive.
The 220LTO appears to be a 5.25" internal drive in an external case, which is probably exactly what it is. Similar to its 420LTO cousin, the 220LTO advertises an operating power consumption of 18 watts. The 220LTO's capacity is half that of the 420LTO, as it is based on the LTO-1 standard. It has a native uncompressed capacity of 100 GB and transfer rate of 16 MB/s.
Other similarities between the drives abound: both sport a 64 MB memory buffer, which is a good amount; memory buffer is important in tape drives. Also, they both utilize the SCSI Ultra160 interface. SCSI controllers are par for the course on server motherboards so this shouldn't be an issue given the drives' typical application. Finally, both drives are a bit loud when operating, but due to their intended use this shouldn't be much of a problem - people probably won't be working in the same room with them, for the most part.
As noted above, these Tandberg LTO drives both include smart inline compression hardware. This hardware is set up to detect files that won't compress well and bypass the hardware compression scheme to allow for more speed when it isn't needed. Files that won't compress well with the inline hardware would be previously compressed files, such as video files or software-compressed files like .ZIP or .RAR archives. While software compressed files use much less space, Tandberg's inline hardware compression works in real time and is much faster than compressing files before archiving them.
slide show: Tandberg 420LTO and 220LTO Streamers