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If Something Goes Wrong

Resolving a hardware conflict

the computer’s Central Processing Unit (CPU). It also needs a direct channel to the computer’s memory to store information as it works. These channels of communication are commonly referred to as system resources.

Interrupt Request Channel

The channel to the CPU is called an Interrupt Request (IRQ) because it interrupts what the processor is doing and requests some of the processor’s time. If two or more devices use the same IRQ, the processor does not know which device is asking for attention. This causes a hardware conflict.

Direct Memory Access

Similarly, the data required by the device is stored in a specific place or address in memory called the Direct Memory Access (DMA). The DMA provides a dedicated channel for adapter cards to bypass the microprocessor and access memory directly. If two or more devices use the same DMA, the data required by one device overwrites the data required by the other, causing a hardware conflict.

Resolving conflicts

There are three things you can do to resolve hardware conflicts:

❖Disable the device.

For an older device, remove it from the computer.

❖Disable another system component and use its resources for the new device, see “Fixing a problem with Device Manager” on page 217.

❖Reconfigure the device so that its requirements do not conflict. Refer to the device’s documentation for instructions about changing settings on the device.