Abit AT7 User Manual page 64

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You can assign an IRQ for the either PCI or AGP VGA or Disabled.
Assign IRQ For USB:
Two options are available: Disabled or Enabled. The default setting is Enabled. If you need free up
another IRQ, you can choose to disable this item to an IRQ. However, some situations in Windows
may cause the USB port to malfunction or experience other problems!
PIRQ_0 Use IRQ No. ~ PIRQ_3 Use IRQ No.:
Eleven options are available: Auto, 3, 4, 5, 7, 9, 10, 11, 12, 14, 15. Default setting is Auto. This item
allows the system to automatically specify the IRQ number for the device installed on PCI slots. This
means that the system can specify the fixed IRQ number for the device installed on the PCI slots (PCI slot
1 to PCI slot 6). This is a useful function for when you want to fix the IRQ for a specific device.
For example, if you want to move your hard disk to another computer and don't want to re-install
®
Windows NT or Windows
computer to fit the original computer settings.
This feature is for the operating system that will record and fix the PCI configuration status if you want to
change it.
For the relations between the hardware layout of PIRQ (the signals from the VIA VT8233A chipset),
INT# (means PCI slot IRQ signals) and devices, please refer to the table below:
SIGNALS
PIRQ_0 Assignment
PIRQ_1 Assignment
PIRQ_2 Assignment
PIRQ_3 Assignment
! USB 2.0 used INT D, INT B and INT C.
! PCI slot 2 shares IRQ signals with the AGP slot.
! PCI - 1 and USB controllers share an IRQ.
! If you want to install two PCI cards into those PCI slots that share IRQ with one another at the
same time, you must make sure that your OS and PCI devices' driver supports the IRQ sharing
function.
! HPT 374 IDE controller is designed to support high-speed and high performance mass storage
devices. Thus, we suggest that you don't connect non-disk devices that use ATA/ATAPI
interfaces, such as a CD-ROM, to HPT 374 IDE connector (IDE3 ~ IDE6). (AT7 Full Version
Only)
AT7
®
2000, you can simply specify the IRQ for the device installed on the new
PCI PCI PCI
Slot 1 Slot 2 Slot 3
INT D INT A INT B
INT A INT B INT D
INT B INT C INT C
INT C INT D INT A
USB LAN
2.0
INT D INT A
INT B x
INT C x
x x
Note
Chapter 3
IEEE HPT AGP
1394 374
INT B INT C INT A
x x INT B
x x
x x
®
95
x
x