CertiGuide to A+ (A+ 4 Real)  9  Chapter 9: Graphic Cards       9  Card Components, Modes and Architecture

Memory 1 Explanation of Common Video BIOS Settings

Upgrading and replacing graphics cards is one of those tasks that everyone has to do, and most people dislike. The simple fact is with modern hardware, it is more likely for the drivers to cause problems than the card itself. In addition, once those drivers and system utilities have been installed, it is a difficult task to remove them again. Taking NVidia as an example, the latest Detonator drivers for Windows not only install the card drivers, they also install the Keystone, Nview and Accuview applications. As can be appreciated, un-installation does not always go smoothly. The last time I attempted to uninstall some Detonators, it rendered my Windows Control Panel Display applet useless, making it near impossible to install different drivers or rectify the problem.

The first step when upgrading or replacing a card should therefore be to get the operating system to a lowest-common-denominator state. In other words, the operating system should be reconfigured to use basic VGA mode (640 * 480, 16 colors, as discussed above). Next, uninstall the drivers using the appropriate method and power off the machine. Using proper antistatic precautions, remove the current card from its PCI or AGP slot, and insert the new card in its place. Power on the machine, and the video bios of your new card should appear on screen. The final step is to install the appropriate drivers for the card into the operating system, and configure the display modes.

In practice, a lot can go wrong with graphics cards. Here are some of the more common issues, and their solutions:

• After powering on the machine, the monitor does not "come alive" but the machine boots up: Check all cabling, especially the D type or DVI connectors from the card to the monitor. If the card is dual head, is the monitor connected to the right connector?
  
  
• After powering on the machine, the monitor comes alive but nothing happens: Check the card is seated properly. Some cards come with a lacquer on the connector pins - removing and reseating the card a few times normally solves this. Also, check that the motherboard slot (AGP or PCI) is free of dust.
  
  
• The video card functions correctly, but benchmark tests show it is extremely slow: Check the AGP Aperture Size in the system BIOS. This defines how much system RAM the AGP bus has access to. An ideal size is between ¹/₃ to ½ system RAM - graphics cards with more onboard RAM can use a smaller value here.
  
  
• Random graphical corruption occurs, or nothing is seen at all: Check the AGP bus speed in the system BIOS. Depending on the motherboard, there will be a selection of 1x, 2x, 4x or 8x. Do not select a higher speed than the card supports.

It is also good practice to ensure the latest BIOS updates are installed (for both the motherboard and graphics card), and the latest drivers for all system components. Quite often two components that may appear to be unrelated will cause problems for no apparent reason. A comparable issue is the existing incompatibility between SoundBlaster 1024 sound cards, and Via chipsets. Installing a hard drive to the second IDE chain with the aforementioned hardware configuration often results in the continuous corruption of data.

Innovative graphics cards (and even some older ones), especially those from ATI and NVidia often fall foul of bad drivers. Keep checking the manufacturer’s website for updates. A classic example of this is the issue with Nvidia’s 22.xx Detonator drivers. Due to some shoddy quality assurance testing, the drivers in question were released with some serious flaws. Over 20,000 posts in their support forums later, Nvidia accepted the issue and re-released the drivers.

If issues with a card continue to occur, test it in another machine - preferably with a different operating system. This will help to narrow down the cause of the issues. By using a different machine, the technician can verify that the problems are not caused by hardware incompatibilities. For example, Windows 2000 seems to have a problem using the GeForce 4 TI4200 Nvidia card, as the text-based portion of Windows Setup crashes when switching between screen modes. A work around that has been discovered (that no technician would like a user to do) is to use an alternative card through the text-based setup. When Windows Setup reboots prior to the graphical setup starting, the original GeForce 4 card can be reinstalled to be detected during plug and play installation.

Using a different operating system will assist the technician in determining if the issue is with a specific version of the operating system or the driver for the hardware. This is one of the reasons Microsoft recommends using hardware that is shown to be pre-tested and compatible with Windows, by checking the device in question is listed on the HCL (Hardware Compatibility List) www.microsoft.com/hcl.

Memory 1 Explanation of Common Video BIOS Settings