Benchmarking graphics cards is a time-consuming affair. A lot of games require manual testing with Fraps, and since driver updates make historical data obsolete, cards usually have to be re-tested for each review. That's why you usually only see relatively recent offerings compared.
Of course, if you have an inordinate amount of time on your hands—not to mention dedication—you can do what Hardware.info did: gather 64 different cards dating back to the Radeon HD 3000 and GeForce 8000 series, benchmark every last one of them, and gather the numbers in a single data set.
If you've ever wanted to know how your old GeForce 9800 GT compares to the new 7770, or how much faster Nvidia's GeForce GTX 660 is than the old Radeon HD 3870, now's your chance. Games tested include Battlefield 3, Dirt: Showdown, and Spec Ops: The Line, and you can view the data either in one big graph or in smaller charts that compare different GPU generations from the same vendor.
It's too bad Hardware.info didn't go inside the second like we do on TR. Still, the work is impressive—and pretty handy for folks who don't upgrade very often. Seeing all of these successive leaps in performance also makes me a little sad that seven-year-old consoles are still holding game developers back. If only today's games were designed with just the PC in mind...