Dell 530 manual Memory Address Conflicts, Interrupt Assignment Conflicts, Used/Available

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)

Solving Problems

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