The Inquirer heard NVIDIA isn't able to clock the GeForce 7900 GTX as high as it wanted. This GPU is basically a 90nm GeForce 7800 GTX (G70) with likel 24 pipelines:
It will use GDDR 3 memory running at 800MHz, with a 1600 MHz memory clock. In the case it ends up with 24 pipes it won't be enough to touch the R580, Radeon X1900 XTX performance crown. If Nvidia did put 32 pipes in G71 chip this would make its chip as a much better competitor and will make ATI run hard for its crown. We think that Nvidia could win most of the benchmarks with 32 pipes.
The core will be clocked at 650MHz and according to the rumours this card won't be able to beat the Radeon X1900 XTX. So NVIDIA decided it will use aggressive pricing to capture the market.
The price of the GeForce 7900 GTX is allegedly 'only' $499.