Abit PX5, Руководство пользователя

Страница: 77 / 90

General Discussion about HDD Installation E-1
Appendix E General Discussion
about HDD Installation
Most of the present HDDs use IDE interface. Installing an IDE hard disk does
not require a huge amount of intelligence like installing the driver for a SCSI hard disk,
but this means that the user often must install the hard disk by himself and cope with
all the problems he may encounter. Here, we will try to help you solve these possible
problems.
The data stored in the hard disk are accessed through a chipset located on the
mainboard. You probably often hear about the PIO mode, Master mode or DMA
mode of HDD. These modes reflect the way data is transferred from and to the IDE
drive and the mainboard.
What is the PIO mode? When the system needs to access hard disk data, the
CPU delivers input/output (I/O) orders through the chipset on the mainboard to the
hard disk drive, and than puts these data into the system memory. This is the PIO
mode.
What is the Master mode? When the system needs to access hard disk data,
these data are directly accessed from the hard disk by the chipset on the mainboard
(using a DMA or a PIO mode), and then the data is put into the memory. In this case,
the CPU does not participate in the data transfer.
What is the DMA mode? Usually, DMA mode refers to accessing the hard disk
data by the chipset, it does not refers to data transfer mode.
Here are some examples of data transfer rates for IDE HDD with PIO interface:
PIO Mode 0 The fastest data transfer rate reaches 3.3Mbyte/sec
PIO Mode 1 The fastest data transfer rate reaches 5.2Mbyte/sec
PIO Mode 2 The fastest data transfer rate reaches 8.3Mbyte/sec
PIO Mode 3 The fastest data transfer rate reaches 11.1Mbyte/sec
PIO Mode 4 The fastest data transfer rate reaches 16.6Mbyte/sec