- If the card requires it, verify that the card is properly connected to the power
supply using one of the power supply’s connectors. Most video cards that
require power use the same type of power supply connector as a hard disk drive. - Verify that the video card has not been assigned system resources that had already
been assigned to another conflicting device. Typically, video cards are not assigned
IRQs, but check anyway; the card you are troubleshooting may just be one of the
ones that do. Use the Windows Device Manager to check on this. If the video card
has either a redXor a yellow exclamation mark by it, there is a problem with
either a device driver or a system resource conflict. - Verify that the device drivers are installed. You may want to reinstall the
device drivers before taking any other more drastic measures. Always use
the device drivers that came with the video card or that you downloaded
from the manufacturer’s Web site. Avoid using the library drivers that come
with Windows, as they are often out of date and can cause more problems. - Check the documentation of the video card. Many cards have specific
requirements for the BIOS settings of the PC. If this is the case, reboot the
PC and access the BIOS’ configuration data by pressing the key (typicallyF1,
F2, orDEL) during the boot sequence to enter the BIOS Startup program and
the CMOS setup. Verify that the BIOS settings are correct for the video card.
Often the Hidden Refresh, Byte Merge, Video BIOS shadow and cache RAM,
VGA Palette Snoop, and DAC Snoop settings may need to be disabled. If you
change any of the CMOS settings, be sure to save them before exiting. - If the above steps do not solve or isolate the problem, it’s time to call technical
support at the video card manufacturer or check with the reseller.
Determining the Type of Video Card in a PC
If you are in doubt about the type of video card installed or in use in a PC, use the DOS
Debug utility, shown in Figure 12-7, which is included with virtually all versions of
Windows. To use the DEBUG command to display the video card information on your
PC, follow these steps:- Open a MS-DOS prompt or command line.
- Typedebugand pressENTER. A dash prompt is displayed.
- Enterd c000:0010as shown in Figure 12-7.
- After the first block of data is displayed, look at the text translation of binary
data on the right side of the display. If the video card data is not shown, typed
and pressENTERto display the next block of memory. - The video data should appear in either the first or second blocks.
(^276) PC Hardware: A Beginner’s Guide