crookedvulture writes: Slashdot's early coverage of AMD's dual-GPU Radeon HD 7990 relied on data collected with Nvidia's FCAT tools, which capture frames just before they hit the display. FCAT is great for quantifying smooth frame delivery, but it doesn't track interruptions earlier in the pipeline that can produce perceptible jitter in the game animation. Those interruptions can be measured with Fraps, correlated with FCAT data, and complemented with video samples to achieve a much deeper understanding of actual performance. Combining those tools to evaluate the 7990 reveals microstuttering that produces choppier gameplay than a single-GPU Radeon with half the theoretical horsepower (and a much lower price). AMD has prototype frame pacing software that can smooth out the stuttering in some games, but there's no timetable for its release. Right now, you're better with the $400 Radeon HD 7970 than you are with AMD's $1000 flagship.