The GeForce 7800 GTX launches today; and NVidia expects boards to ship now from board partners such as Asus and Chaintek at a retail price of around $599. The reference board we tested was a single-slot PCI- Express board equipped with 256MB of 600-MHz DDR3 memory and dual DVI outputs
Running at 430 MHz, the new chip clocked a bit slower than the GeForce 6800 Ultra--NVidia's previous high-end graphics chip. NVidia boosted the new chip's processing power in a couple of ways. First, NVidia's chip designers added more pipelines for processing pixel and vertex shaders--short programs that the graphics chip runs to create realistic 3D graphics. The 7800 chip has 8 vertex shader pipelines and 24 pixel shader pipes, whereas the chip in 6800 Ultra boards contains 6 vertex pipes and 16 pixel pipes. The extra pipelines account for much of the new chip's high transistor count.
At the same time, NVidia's engineers analyzed how those pipelines work and optimized them to run typical game code faster than before. The result, NVidia says, is that the 7800 GTX can outrun the 6800 Ultra pipe-for-pipe.
The GeForce 7800 GTX reference board we tested set new speed records in almost all of the PC World Test Center's gaming tests--an impressive feat in of and itself. For example, in our Doom 3 test with antialiasing, the 7800 GTX posted frame rates of 65 and 42 frames per second, respectively, at 1024 by 768 and 1600 by 1200 resolution. By contrast, a previous speed leader, ATI's $500 Radeon 850 XT Platinum Edition, managed only 52 and 31 fps, respectively, in those same tests.
Results in our Far Cry test were almost as dramatic. The 7800 turned out 50 fps running at 1600 by 1200 resolution with antialiasing on. The next fastest board, a GeForce 6800 GT, cranked out 34 fps; and ATI's 850 Platinum managed only 17 fps. Midrange graphics boards like NVidia's GeForce 6600 GT, which costs around $200, complete the same Far Cry test at about 19 fps.
In addition, the 7800 GTX supports NVidia's SLI technology, which allows you to run two identical graphics boards in a system built to permit such doubling up, dramatically boosting performance in some games. We didn't get a chance to test an SLI configuration, and we probably wouldn't have seen much of a benefit on our current graphics test bed anyway, since nearly every game in the test suite already seemed to be running as fast as the CPU could pump out game data.
At around $600 for one card ($1200 for an SLI configuration) the GeForce 7800 GTX is priced out of the range of all but the most well-heeled gamers, but our tests demonstrated that it delivers pretty good value. That NVidia managed to fit everything into a single-slot board cooled by a reasonably quiet fan is doubly impressive.
|NVidia GeForce 7800 GTX |
Preproduction model (not rated)
Ultrapricey new graphics board sets new speed record and delivers good bang for the megabuck.