Dell PRECISION 530 - Manual (Page 207)

Solving Problems 207
Memory Address Conflicts
Memory address conflicts occur when two or more devices try to access the
same address in the upper memory blocks. For example, if a network
expansion card and an expanded-memory page frame are assigned an
overlapping block of addresses, a memory address conflict arises. As a result,
when you try to log in to the network, the operation fails.
To resolve this type of conflict, you can change the address of one of the
devices. For example, in the case of the network expansion card and
expanded-memory page-frame address conflict, you can move the network
card to an address block in the range of CC000h through D0000h. To
reassign the expansion card's address block, refer to the documentation for
the card.
Interrupt Assignment Conflicts
Problems can arise if two devices attempt to use the same IRQ . To avoid
this type of conflict, check the documentation for the default IRQ setting
for each installed expansion card. Then consult the following table to
configure the card for one of the available IRQs.
NOTE: The following table lists default IRQ settings. In computers with Plug
and Play capabilities, you can modify the defaults. If you install a Plug and
Play card in a Plug and Play computer, the computer automatically selects an
open IRQ if any are available.
D e f a u l t I R Q A s s i g n m e n t s
IRQ Used/Available
IRQ0 Used by the system timer
IRQ1 Used by the keyboard to signal that the output buffer is full
IRQ2 Used by interrupt controller 1 to enable IRQ8 through IRQ15
IRQ3 Used by serial port 2
IRQ4 Used by serial port 1
IRQ5 Available
IRQ6 Used by the diskette/tape drive controller
IRQ7 Used by the parallel port
IRQ8 Used by the real-time clock (RTC)