We've been waiting quite a while for ATI's new generation of graphics chips. It's no secret that the R500-series chips are arriving later than expected, and fans of the company have nervously speculated about the cause of the delay. ATI chose to build its new series of graphics chips using 90nm process technology, and going with new process tech has always been risky. Some folks fretted that ATI may have run into the same sort of problems at 90nm that made Intel's Pentium 4 "Prescott" processors famously hot, power hungry, and unable to hit their projected clock speeds. In a related vein, others fussed over rumors that ATI's new high-end R520 architecture was "only" 16 pipes wide, compounding the process technology risk. If the R520 couldn't hit its clock speed targets, it could have a difficult time keeping pace with its would-be rival, NVIDIA's GeForce 7800, whose wider 24-pipe design makes it less dependent on high clock frequencies. As the weeks dragged on with no sign of ATI's new GPUs, the rumor mill began circulating these concerns ever more urgently.

Two weeks ago today, Rich Heye, VP and GM of ATI's desktop business unit, stood up in front of a room full of skeptical journalists and attempted to defuse those concerns. The problem with R520, he told us, with neither a snag caused by TSMC's 90nm process tech nor a fundamental design issue. The chip was supposed to launch in June, he said, but was slowed by a circuit design bug--a simple problem, but one that was repeated throughout the chip. Once ATI identified the problem and fixed it, the R520 gained 150MHz in clock frequency. That may not sound like much if you're thinking of CPUs, but in the world of 16-pipe-wide graphics processors, 150MHz can make the difference between competitive success and failure.

With those concerns addressed, ATI proceeded to unveil not just R520, but a whole family of Radeon graphics products ranging from roughly $79 to $549, based on three new GPUs that share a common heritage. It is one of the most sweeping product launches we've ever seen in graphics, intended to bring ATI up to feature parity with NVIDIA--and then some.

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