3d-only cards process 3d-rendering data from certain programs so that the CPU doesn't have to do as much work. They have no 2d capabilities and need a video card to function, but can tremendously increase the performance of 3d games and applications.

Most 3d-only cards use a single PCI expansion slot, but there are also a few AGP 3d-only cards. 3d-only cards based on the 3dfx Voodoo2 chip can be connected together to achieve nearly double the performance in some applications.

Unless you are a devoted gamer or use 3d rendering applications, you probably don't need a 3d-only video card. The sole purpose of these cards is to handle 3d processing so that your CPU won't have to. They have no 2d capabilities at all, and for this reason cannot be substituted for a regular 2d or 2d/3d video card. Most of the 3d-only cards available at this time use a single PCI slot.
First generation 3d-only cards were capable of speeds that most 2d/3d cards couldn't compare to. Now, however, the 2d/3d cards are catching up in performance. Since most people don't want to pay $100 to $300 for a card that only handles 3d processing, many manufacturers are abandoning 3d cards in favor of 2d/3d chipsets for regular video cards that will satisfy mainstream consumers. At the time of this writing, 3d-only cards are falling in price significantly.

A Phillips screwdriver and about 15 minutes of time are required to install a 3d-only card.

Click here for a list of links to 3d-only card manufacturers.
 

the installation

1. Make sure the computer is turned off.

2. Carefully disconnect all of the cables from the back of your computer, place the computer on a stable working platform, and remove the outer case. Discharge any static electricity from your body by touching the computer's power supply.

3. Locate a free expansion slot that matches your new 3d card's interface (PCI or AGP). If the slot you have selected was previously unused, you will need to remove the expansion slot cover (a metal strip blocking the opening next to the expansion slot) by removing the screw holding it in place. Remove your new 3d card from its anti-static bag. Line up the edge of the card containing the metal contacts with the slot and push the card in firmly with its metal plate facing the back of the computer. If you find it too difficult to push the card in directly, insert one corner of the card into the expansion slot, then push the rest of the card into place. Secure the card with the previously removed screw.

   

4. Replace the outer case and move the computer back to its original location. Reconnect all of the cables, but connect the monitor cable to the 3d card instead of the video card.

5. Use the included pass-through cable to connect the video card to the 3d card.

6. Start up the computer. If nothing is displayed on the monitor, turn off the computer and check all of the connections. If you still can't get video output, contact the manufacturer. Windows should recognize the new 3d card and attempt to install the drivers for it. It may prompt you to insert the Windows 9x CD or the CD or floppy disk that came with the 3d card.

7. Click on the Start button, move the cursor to Settings, and click on Control Panel. Double click on the System icon. Click on the Device Manager tab, then expand the Display adapters category. There should now be an entry for your newly installed 3d card. If there is no entry, or if the entry has a yellow circle with an exclamation mark next to it, your sound card is not configured properly or there is a hardware conflict of some sort. Consult the manual that came with your 3d card and/or use the Windows Troubleshooting Guide to resolve the problem. To access the Troubleshooting Guide, click on the Start button, then click on Help. Troubleshooting should be listed in the table of contents.

8. Install any software that came bundled with the 3d card.