Separate I/O types: Keep write-intensive and read-intensive environments on separate physical devices.
Keep random activity and sequential activity on separate devices.
Match the RAID level's characteristics to the volume in question; for example, don't put a write-intensive application on a RAID 5 volume.
Use Fast drives, such as the new 10K-revolutions-per-minute (RPM) drives.
Use SCSI, not IDE or EIDE. SCSI's extensibility and performance far exceed IDE's for server applications (even EIDE maxes out at 17MBps data transfer rates).
Use a RAID volume (such as 0) for your page file to enhance virtual memory performance.
Use multichannel hardware-accelerated disk controllers.
Keep an eye out for Intelligent I/O (I2O) devices, which offload I/O processing to dedicated CPUs on peripheral cards such as RAID and network controllers. This approach achieves much greater throughput with a small fraction of the impact on the system's main CPU(s).