This is not as important in practice as when using only a single disk drive. When RAID controllers with several hard disks are used, the PCI bus becomes the bottleneck. The benefits of the faster 133 MHz bus are not achieved.

Cache

Cache controllers use integrated cache memory to retain the data that is being transferred. This speeds up the transfer of data whenever data already stored in the cache is requested for a second time. Standard DDR-RAM is used for cache memory.

Hot-Plugging

Hot-plugging means that hard drives may be swapped while the system is running. The computer does not have to be switched off. This does not work with RAID-0.

Test Results In Detail

Five of the eight RAID controllers tested have a very low feature count. There is also some room for improvement as far as service is concerned.

The Highpoint Rocket Raid 404 delivers the highest performance of all of the models tested. In RAID-5 mode, the Escalade 7850 from 3Ware proves that data security and high speed are not mutually exclusive.

3Ware Escalade 7850

A maximum of eight Ultra-DMA/ 133 hard disks may be connected to the eight channels of 3Ware's Escalade 7850. The cache controller supports level 5 in addition to the usual RAID modes. This makes the most effective use of disk space. The speed penalty is about 10 percent compared with RAID levels 0 and 1, although, in practice, this will hardly be noticeable. The RAID-0 and RAID-5 results are close together at 56,800 and 56,750 kBytes per second (RAID-0 compared to RAID-5).

3Ware's Escalade 7850 controller earns first place with its good performance and features, and receives the recommendation of the editorial team. However, he Escalade 7850 is the most expensive product of the group by a considerable margin.