HP Vectra XU 6/XXX Optimization Manual page 24

The IDE controller transfers data to or from IDE devices in response to data transfers received
or requested on your PC's PCI bus. The technique used for a particular data transfer with an
IDE device is chosen according to the type of transfer received or requested on the PCI bus. In
this way, the IDE controller ensures that data transfers are optimized between the PCI bus and
the IDE device.
Your PC's IDE controller supports five PIO modes, PIO Mode 0 - 4, and three DMA modes,
DMA Mode 0 - 2. Higher numbered modes offer increased data transfer rates than lower
numbered modes. Not all IDE devices support all of these modes. When transferring data with
an IDE device, the integrated IDE controller will select the highest numbered mode supported
by the IDE device.
Data transfer rates for all of these modes are given in the table below.
Transfer Mode
PIO Mode 0
PIO Mode 1
PIO Mode 2
PIO Mode 3
PIO Mode 4
DMA Mode 0
DMA Mode 1
DMA Mode 2
PCI Master Capability
The integrated IDE controller transfers data with your PC's processor and memory through the
PCI bus. PCI devices fall into two categories: slaves and masters. A PCI slave is a device that
can only respond to transfers or requests made by another PCI device — it cannot initiate
transfers. A PCI master is able to initiate transfers and to take control of the PCI bus while a
transfer is being made.
Maximum Transfer Rate
3.33 MB per second
5.22 MB per second
8.33 MB per second
11.1 MB per second
16.7 MB per second
4.2 MB per second
13.3 MB per second
16.7 MB per second