Tyan Computer GX21 - Manual (Page 80)

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IDE HDD Block Mode
The IDE HDD Block Mode feature speeds up hard disk
access by transferring data from multiple sectors at once
instead of using the old single sector transfer mode. When
you enable it, the BIOS will automatically detect if your hard
disk supports block transfers and configure the proper block
transfer settings for it. Up to 64KB of data can be transferred
per interrupt with IDE HDD Block Mode enabled.
If you disable IDE HDD Block Mode, only 512 bytes of data
can transferred per interrupt. This degrades performance
quite a bit. For optimal performance, enable this option. The
choices are:
Enabled / Disabled
Note:
Microsoft recommends that WinNT
4.0 users without Service Pack 2 disable IDE
HDD Block Mode as it causes data corrup-
tion.
On-Chip Primary PCI IDE
IDE hard drive controllers can support up to two separate
hard drives. These drives have a master/slave relationship
which is determined by the cabling configuration used to
attach them to the controller. Your system supports two IDE
controllers-- a primary and a secondary-- so, up to four sepa-
rate hard disks can be installed.
PIO means Programmed Input/Output. Rather than have the
BIOS issue a series of commands to effect a transfer to or
from the disk drive, PIO allows the BIOS to tell the controller
what it wants and then let the controller and the CPU perform
the complete task by themselves. This is simpler and more
efficient (and faster).
Your system includes two built-in IDE controllers, both of
which operate on the PCI bus. This setup item allows you
either to enable or disable the primary controller. You might
choose to disable the controller if you were to add a higher
performance or specialized controller. The choices are:
Enabled / Disabled