"Not everybody has an AGP slot. Some OEMs (most notably Compaq), and some lower cost computer manufacturers like to integrate both sound and video on their mainboards. This posses a definite problem for people who want to upgrade their video card to the latest and greatest, this is where 3dfx's V5 5500 PCI steps in. Offering almost identical performance to its AGP sibling the V5 5500 PCI is in an excellent position."
FULL STORY @ SPEEDY3D (http://www.speedy3d.com/reviews/v5_5500pci/01.shtml)