Hardware Reference
In-Depth Information
Figure 4.48. This system uses PCI IRQs from -2 to -4, from 16 to 25, and from 53 to 54.
Note
APIC must be enabled in the system BIOS before you can install x64 editions of Windows.
IRQ Conflicts
If you manage systems that use ISA slots, you might have the potential for conflicts between the IRQ
requirements of add-on cards and the requirements for built-in devices. To learn how to deal with
common sources of IRQ conflicts and to free up the maximum number of IRQs, see the section “IRQ
Conflicts” in Chapter 4 in
Upgrading and Repairing PCs,
19
th
Edition, available in its entirety on the
DVD packaged with this topic.
DMA Channels
Communications devices that must send and receive information at high speeds use direct memory
access (DMA) channels. Conflicts between devices needing to use the same DMA channel were
common on systems using ISA slots but are no longer an issue on modern systems.
To learn more about DMA channels and possible conflicts on older systems, see “DMA Channels” in
Chapter 4 in
Upgrading and Repairing PCs,
19
th
Edition, available in its entirety on the DVD
packaged with this topic.
I/O Port Addresses
