On some systems you will find an option in the system BIOS called block mode.
Block mode is a performance enhancement that allows the grouping of multiple read or write
commands over the IDE/ATA interface so that they can be handled on a single interrupt.
Interrupts are used to signal when data
is ready to be transferred from the hard disk; each one, well, interrupts other work being
done by the processor. Newer drives, when used with a supporting BIOS allow you to
transfer as many as 16 or 32 sectors with a single interrupt. Since the processor is being
interrupted much less frequently, performance is much improved, and more data is moving
around with less command overhead, which is much more efficient than transferring data one
sector at a time.
Note: Some systems can
have trouble running disks in block mode, even if they are supposed to allow it. You may
have better luck with the drive or system if it is disabled.
Next: IDE/ATA
Configuration and Cabling
