X-bit Labs has written one of the first previews of NVIDIA's upcoming GeForce GTX 465, you can check it out over here. The site concludes the GeForce GTX 465 won't be a success in its current form, as it's not an attractive buy when compared to the slightly more expensive Radeon HD 5850.
The GF100 is already inferior to its predecessor in terms of texture-mapping units, and there are only 44 of them left in the GeForce GTX 465 – a ridiculously small number even compared with the GeForce GTX 275. This dramatic reduction in GPU resources will surely affect the performance of the new card in 3D applications. It might be justified if it helped improve the frequency potential. However, the GPU clock rates are the same as with the GeForce GTX 470, namely 607/1215 MHz. The RBE subsystem is all right: it is equivalent to that of the G200b-based cards and represented by 32 raster operators. The memory bus is only 256 bits wide, which is not good at all, even though the GeForce GTX 465 uses GDDR5. The GeForce GTX 275 had a peak memory bandwidth of 127 GBps with GDDR3, but the new card is slower at 102.7 GBps. Thus, we cannot expect the GeForce GTX 465 to perform fast at high resolutions and the reason is its low memory frequency of only 802 (3208) MHz. That’s not serious for modern GDDR5 memory chips.