PC Hardware A Beginner’s Guide

If the answer to any of these questions is yes, you need to review and modify the

system resource assignments to resolve the problem:

NOTE: If the new device is a sound card, you can just about count on the problem being a system

resource conflict.

1. Write down the current resource settings and assignments, including those in
   the BIOS’ configuration data (see Chapter 6 for information on how to access the
   BIOS configuration). It is also a very good idea to run a virus checker on the
   system before making any changes. Some viruses can cause damage that
   will show up much like a system resource problem (see Chapter 22 for more
   information on viruses).


2. Open the Windows Device Manager and select the device (expansion card) that
   was recently added to the PC. If the device has a yellow exclamation mark or
   red X symbol in front of its name, it is conflicting with another device or its
   configuration cannot be resolved by the BIOS or operating system.


3. Open the Properties window and display the Resources tab information. At
   the bottom of the display (refer to Figure 11-21), there should be information
   regarding the conflicting device.


4. At this point, you will need to change the conflicting resource (probably an
   IRQ—and definitely an IRQ if the device is a PCI card) to another available setting.
   If there are no IRQs available, you may need to share with another device, but
   make sure that the sharing device will not be in use at the same time as the new
   device. You may need to change the settings on the expansion card using jumpers
   or DIP switches using the card’s documentation as your guide to the new values or
   positions. The system BIOS of the PC may support the reassignment of IRQs (for
   PCI slots) in the setup program. Most resource conflicts exist between expansion
   slots, and many can be resolved in the BIOS settings.

Resolving Resource Conflicts with Plug-and-Play Devices

Plug-and-Play (PnP) devices can cause IRQ conflicts because the PnP processes in the

operating system and BIOS may not detect all other devices, or it may not correctly detect

a new device. PnP devices are configured after all other devices are assigned resources

during the boot cycle, so there is always the chance for a conflict.

To resolve a resource conflict on a PnP device:

1. Remove the new device from the Windows Device Manager and restart the PC
   to see if the problem was a one-time occurrence.


2. If the conflict is not resolved by rebooting the system, verify that the most
   current device drivers are installed. Visit the manufacturer’s Web site to find
   the latest drivers and install them on your PC. The manufacturer may also have

(^250) PC Hardware: A Beginner’s Guide