When selecting a graphics card for a motherboard, the most important factor is the power or "watts" the card requires. The watts a card requires can be found on the product's packaging. Other factors include the type of graphics processor (GPU) the card has, the size and type of connector on the motherboard, and whether or not additional features like 3D support or overclocking are desired.  Not only that, CPU and power supply plays a major role in choosing a GPU. Pairing a low level with a mid-level GPU may cause bottleneck issues. Plus, a lower watts power supply maybe not be enough to juice your GPU.