There are three main types of graphics cards, PCI, AGP, and PCI-E, and they all depend on what kind of add-on slots your system has.
PCI cards are a dying breed since the PCI bus simply isn't able to keep up with the demands of PC games these days. But they're also the closest thing to a universal card there is.
AGP cards are probably the most common, but are also on their way out. There were several revisions of the AGP bus, including two different voltage settings which can mean the difference between a card working and not working. A 3.3V card isn't going to work in a 1.5V slot and vise versa.
PCI-E is the newest "member" of the club. Faster than the other two, and with greater potential for growth, this is the form you're going to be seeing most video cards in for several years to come. While I believe it's backwards compatible with PCI cards, it's not compatible with AGP cards.
So, the first step is figuring out what kind of slots your system has, then finding a card that will work in that particular slot.
Will any graphcis card work with every motherboard? Because my graphics card is getting old and i want to get a better one. So are their specific graphics cards you can use for your motherboard or can any work?
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