The Performance-Mainstream category seems to be the only one where your shopping choice is obvious. We recommend you the ATI Radeon HD 4870 which was ahead of the Nvidia GeForce GTX 260 in each of our seven games at both resolutions (1680x1050 and 1920x1200). We should note that we benchmarked the older version of the latter card that had 192 shader and 64 texture processors active. The newer version with 216 and 72 such processors wouldn’t be any faster than the successful and well-balanced solution from ATI, though.
The ATI Radeon HD 4850 is superior in the bottom sector of this market segment. This graphics card has already earned high popularity among PC gamers. Dead Space is the only game where it is slightly inferior to the Nvidia GeForce 9800 GTX+, yet it provides a comfortable frame rate even then. In other words, the Nvidia G92 architecture has exhausted its potential. Transitioning to a thinner tech process or increasing clock rates can but delay the agony for a little while. Nvidia definitely needs a new-generation mainstream GPU capable of competing with ATI’s RV770.
Thus, the choice in the Performance-Mainstream category is simple: you should prefer the ATI Radeon HD 4870 or, if you want to save a little, ATI Radeon HD 4850. Both solutions boast a superb price/performance ratio as opposed to Nvidia’s products, especially to the GeForce GTX 260 which is no better than the Nvidia GeForce 9800 GTX+ in some tests.