ATI Technologies (905/882-2600, http://www.atitech.com ), whose Rage II and Rage Pro chips drive the displays in Apple's G3 Macs, has developed a faster processor for a new generation of graphics accelerators. The Rage 128 features an internal 128-bit data path, compared with the 64-bit path in earlier Rage chips, along with other performance enhancements.
ATI plans to offer two versions of the chip, one for its own accelerator cards, and the other for system motherboards. The former features a 128-bit path to video memory, while the latter uses a 64-bit external path.
The Rage 128 is a complex piece of engineering, packing 8 million transistors, compared with about 3 million in the Rage Pro. The Rage 128 incorporates a 250MHz digital-to-analog converter (DAC), which produces the signals that drive the display. Earlier Rage chips lacked an integrated DAC, which then had to be implemented as a separate piece of silicon.
The chip features several enhancements designed to accelerate 3-D-graphics performance, including 32-bit Z-buffering and single-pass multitexturing. ATI has also added support for Open GL 1.2, a set of standard 3-D-graphics routines that is gaining favor among software developers. Because the Open GL operations are encoded on the chip, software that supports the standard should run much faster on systems equipped with the Rage 128. Another new feature, four-tap filtering, offers smoother interpolation of QuickTime movies that have been enlarged from their original size.
ATI plans to use the chip in three new graphics accelerator cards: the Nexus 128, Xclaim VR 128, and Rage Orion. The company has also introduced the Xclaim 3D Plus, a $179 board–fea;uring the older Rage LT Pro chip–de;igned for use with digital flat-panel displays (see "LCD Monitors Get Bigger and Cheaper," elsewhere in this section).
The $299 Nexus 128, the successor to the $599 Nexus GA, features 32MB of memory and a maximum full-color 3-D resolution of 1,920 by 1,200 pixels. The Nexus GA, by comparison, offered 8MB of RAM and a maximum 3-D resolution of 1,024 by 768 pixels. The new board also adds QuickTime acceleration, which was previously available in other ATI graphics cards but not in the Nexus GA.
The Nexus GA used an external DAC and costly Windows RAM. ATI says the performance improvements in the new chip allowed its engineers to replace the Windows RAM with less-expensive synchronous RAM.
The $229 Xclaim VR 128 features 16MB of SDRAM, offering a maximum full-color 2-D resolution of 1,600 by 1,200 pixels and a maximum 3-D resolution of 1,280 by 1,024 pixels. The price includes ATI's Xclaim TV, a TV tuner that works with the board's video-in port. By comparison, the $399 Xclaim VR sported just 8MB of memory and lacked the bundled tuner.
The Rage Orion board, which is targeted at Mac gamers, will compete with Micro Conversions' Game Wizard. The $229 board features 32MB of memory and a maximum full-color resolution of 1,900 by 1,280 pixels.
ATI claims that the Rage 128 offers game performance comparable to that of 3Dfx's Voodoo 2 chip, which powers the Game Wizard and numerous PC graphics boards. ATI is also positioning the Rage 128 against 3Dfx's new Voodoo Banshee chip, which offers 2-D and 3-D acceleration; the Voodoo 2 is limited to boosting 3-D game performance.
The Xclaim 3D Plusthe only new board to feature an older ATI chipwill power digital flat-panel displays as well as analog CRT or LCD monitors.
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