What is a 3D video card?

The new market for 3D accelerators and 3D acceleration features has spawned a large crop of 3D video cards with varying capabilities. There are several different approaches that are taken to providing a system with 3D capabilities. While the available cards and technologies are changing rapidly, you will generally find that the cards on the market break out as follows:

* 2D Only (Conventional) Cards: These are regular video cards that do not incorporate any special 3D acceleration functions. Usually these are either older cards, or newer cards that are optimized for 2D performance. When using a card of this type, it is necessary to pair it with a 3D card to obtain 3D acceleration functions.

* Dedicated 3D Cards: These are accelerators that are designed only for 3D hardware functions. Since they do not do conventional 2D acceleration, they need to work with a 2D card in most cases to deliver good 2D+3D performance. Most of the higher-quality 3D cards are of this variety. They typically use a feature connector to connect directly to the 2D card. This lets the 3D card perform its acceleration functions to provide a video stream without requiring its own RAMDAC or bus control logic. This is generally the best solution for high-end graphics but it incurs the cost of two video cards.

* Combination 2D+3D Cards: In an effort to tackle the cost problem of using an additional, separate card for 3D acceleration, many companies are developing cards that perform both 2D and 3D functions. For many users, this is a good, cost-effective compromise. Most of these cards provide from moderate to good 2D performance, and support for some to most of the 3D acceleration features. However, like most compromises, these cards typically don't provide the level of performance or feature support that dedicated 3D cards do. It is important to research these cards well, since many of them support only a small subset of the 3D acceleration features found on 3D cards.