Fast and Secure: A Comparison of Eight RAID Controllers

Performance And Security

You will achieve a considerable boost in hard disk performance with a RAID-0 configuration. The speed increase is achieved by reading and writing on more than one hard disk at the same time. There is no redundancy, which means that you will lose your data if only one hard disk should fail. The risk of losing your data is even greater than in a normal hard disk setup. With RAID-0, there are at least two hard disks that could go wrong.

A RAID-1 system offers the PC user an increased level of security, because it protects against data loss in the event of a drive failure. If a failure occurs, the remaining drive carries on unimpaired.

RAID-5 arrays protect against data loss, as well as providing faster throughput. Your data is distributed across at least two hard disks, with error correction information stored on an additional disk.

If you require constant availability from your hard disk system, you should choose a hot-pluggable controller. By using optional hard disk caddies, faulty drives can simply be exchanged while the system continues to operate. All the products we tested provide this option.

Limited Scalability

As far as pure data transfer is concerned, modern IDE drives are no longer inferior to SCSI drives - and they are considerably cheaper. But SCSI technology is not yet obsolete. The choice of drive depends on the type of application. A SCSI configuration is a few percent faster overall - particularly in multi-user environments where fast access to a database is needed. The SCSI architecture has an advantage in instances when you expect to expand the system at a later date.

The scalability of an IDE RAID system is not in the same league. Cable lengths are limited to 43 centimeters, and only two IDE devices may be connected to any one channel. SCSI allows at least seven.

Twice The Performance For Not A Lot More

The main argument in favor of IDE RAID is its good price/ performance ratio. It allows you to achieve a substantial increase in PC system performance and data security for a reasonable cost. For example, a system with two 120 GByte hard disks (Maxtor 4G120J6) and our budget winner Dawicontrol DC-100 Raid would cost you just under $400.