Another configuration concern is which graphics card is labelled as the primary one. If your PC sees only one graphics card when it starts, it uses that card, no questions asked. But if it finds multiple cards installed, your PC's BIOS designates the one that was installed first as the primary graphics card-and uses it to boot up-while designating the other as the secondary card.

You may expect the card you already use to be the primary card and the card you add to be the secondary card. Unfortunately, that doesn't always happen in systems with AGP slots. The BIOS on many AGP motherboards installs a PCI card before an AGP card. If you currently use an AGP graphics card and want to install a secondary PCI card, you may have to use your AGP card as the secondary card.

To determine which card your AGP system will use as the primary one, install your second graphics card and reboot your system. (Always ground yourself-by touching the metal chassis with the PC plugged in-before working inside your PC. Then unplug the system and go to work.) As your system starts, the screen will announce which card it uses to boot; that's your primary card.

If the primary card isn't your AGP card, check your PC's CMOS setup program. Some recent BIOS versions let you select the primary graphics card manually. Or your PC's manufacturer may offer a BIOS update that adds this functionality.

If your PC still won't let you make your AGP card the primary card, its time to capitulate and reinstall it as the secondary card from the outset. But first, you'll have to uninstall it. Make sure you select its Device Manager entry and click the Remove button to delete its listing before turning off the PC and physically removing the card. Then boot your PC and let it set up the PCI card as the primary graphics card. Next, shut down the PC, reinstall your AGP card, boot the PC, and let it set up the AGP card as the secondary card.

The same ideas apply if you have two PCI cards. The PC's BIOS will assign primary and secondary status to specific PCI slots, with primary status typically going to Slot 1. Of course, being able to put any card in any PCI slot is a clear advantage. Check your system documentation to find which PCI slot is Slot 1 on your PC.

By Kirk Steers