HP Vectra VL 5/xxx Series 5 User Manual
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2 System Board
Devices on the PCI Bus
to a channel, it should be in the master position (the connector that is
closest to the system board, unless the markings on the cables state
otherwise).
It is possible to mix a fast and a slow device, such as a hard disk drive and a
a CD-ROM, on the same channel without affecting the performance of the
fast device. The BIOS sends a command to each drive to determine,
automatically, the fastest configuration that it supports. However, in general,
the primary channel cable is recommended for hard disk drives, and the
secondary channel cable for CD-ROM drives.
Transfer Rates Versus
Modes of Operation
The controller supports 32-bit Windows I/O transfers. Five PIO modes, and
three DMA modes are supported. The five supported PIO modes allow the
following transfer rates.
The three DMA modes allow the following transfer rates:
Disk Capacity Versus
Modes of Addressing
The amount of addressable space on a hard disk is limited by three factors:
the physical size of the hard disk, the addressing limit of the IDE hardware,
and the addressing limit of the BIOS. The Extended-CHS addressing scheme
allows larger disk capacities to be addressed than under CHS, by performing
a translation. If the Setup field has been set to
automatic
, the logical block
addressing (LBA) mode will be selected for each device that supports it.
Mode
0
1
2
3
4
Cycle time (ns)
600
383
240
180
120
Transfer rate (MB/s)
3.33
5.22
8.33
11.1
16.7
Mode
0
1
2
Cycle time (ns)
480
150
120
Transfer rate (MB/s)
4.2
13.3
16.7
Cylinders per
Device
Heads per
Cylinder
Sectors per Track
Bytes per
Sector
Bytes per
Device
CHS
64
16
1024
512
528 M
ECHS
64
256
1024
512
8.4 G
LBA
-
-
256 M (=2
28
)
512
137 G