Resolving System Resource Conflicts

Partial Table-of-Contents

This chapter describes the default system resources and how to share an IRQ between two devices. This chapter is only for Windows 98 and Windows 95.

To use devices, the following system resources are required:

• Interrupt request (IRQ): A signal from the devices to the processor. The system has 16 levels of IRQs.
• Direct memory access (DMA): A mechanism to help the overall system performance by transferring data between memory and devices without processor intervention. The system has eight DMA channels.

The IRQ levels, DMA channels, and I/O addresses must be configured without introducing conflict among devices. In most cases, your computer automatically assigns the system resources when you install a new device. Sometimes, however, when you add new devices to your ThinkPad computer, you might exceed the number of IRQs or DMAs allowed in the operating system. In this case, Windows 98 does not allocate the resources correctly, because the resource might already be allocated to another device. This is called a system resource conflict, or contention. This section explains how to resolve such a resource conflict.