Video Hardware - Upgrading and Repairing PCs - page 805

scene), and load-balancing scissor operation (similar to SLI's load-balancing). The ATI
Catalyst driver uses alternate frame rendering for best performance, but it automatically
switches to one of the other modes for games that don't work with alternate frame render-
ing.
Toachievebetterimagequalitythanwithasinglecard,CrossFireoffersvariousSuperAA
(antialiasing) modes, which blend the results of antialiasing by each card. CrossFire also
improves anisotropic filtering by blending the filtering performed by each card.
To use CrossFireX, you need the following components:
• A PCIe motherboard with a CrossFireX-compatible chipset and two PCIe video slots
designed for CrossFireX operation
• A supported combination of ATI CrossFireX-supported cards
Note
For specific models of motherboards, video cards, power supplies, memory, and cases
designed to support CrossFireX, see http://sites.amd.com/us/game/technology/Pages/cross-
firex.aspx .
First-generation CrossFire cards required users to buy special CrossFire Edition cards
that contained the composting engine (an Xilinx XC3S400 chip) and used a proprietary
DMS-59 port for interconnecting the cards. One of these cards was paired with a standard
Radeon card from the same series via a clumsy external cable between the CrossFire Edi-
tion's DMS port and the DVI port on the standard card. Newer CrossFire-and CrossFireX
compatible cards use the PCIe bus or a CrossFire bridge interconnect (similar in concept
to the SLI MIO component) to connect matching cards.
CrossFire and CrossFireX can be disabled to permit multimonitor operation; CrossFire
and CrossFireX cards can also be used to implement physics effects in games that use the
HavokFX physics technology ( www.havok.com ).
Monitors
The monitors typically used with PCs come in a variety of sizes and resolutions and
are typically based on one of two display technologies: liquid crystal display (LCD) or
cathode-ray tube (CRT). Larger displays such as big-screen TVs and projectors can also
use LCD or backlit LED technology but may use plasma or DLP technology as well. This
section discusses the various features, specifications, and technologies used in PC monit-
ors.