nVidia is launching today its new high-end 3D graphics chip, GeForce 7800 GTX, which is based in a totally new core (called CineFX 4.0). Instead of using the "old" GeForce 6800 core and simpling raising its clock, nVidia decide to re-design the way instructions are processed inside the chip. According to nVidia, this led to a performance increase up to 50% in GeForce 7800 GTX compared to a GeForce 6800 Ultra running at the same clock rate – according to the manufacturer, a single GeForce 7800 GTX is faster than two GeForce 6800 Ultra in SLI mode.

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Figure 1: GeForce 7800 GTX.

GeForce 7800 GTX main specs are:

• 24 pixel shader pipelines (against 16 in GeForce 6800 Ultra) and eight vertex shader pipelines (against six in GeForce 6800 Ultra).
• Each one of the pipelines was redesigned, allowing the execution of up to eight MAD (multiply-add) operations per clock cycle. This is the most common operation in 3D games. Because of that, each pipeline can achieve a FP processing performance of 165 Gflops, against 66 Glops in Radeon X850 XT Platinum Edition and 54 Gflops in GeForce 6800 Ultra.
• New anti-aliasing mode called "Transparency Anti-Aliasing" which enhances the image quality in 3D games.
• Image enhancement features for 2D video (de-interlacing, inverse 3:2 and 2:2 pull-down) collectively called PureVideo by nVidia.
• According to nVidia, GeForce 7800 GTX offers up to 60% improvement in HDR (High Dynamic Range) over GeForce 6800 Ultra. HDR feature is used to enhance lightning, and we will explain more about this feature in a moment.
• Power consumption slight inferior than GeForce 6800 Ultra: GeForce 7800 GTX consumes between 100 and 110 W while GeForce 6800 Ultra consumes between 110 and 120 W. If you consider that GeForce 7800 GTX has 36% more transistors than GeForce 6800 Ultra (302 million x 222 million) – which would lead to a power consumption increase –, this new chip is more power efficient.
• Requires a 350 W power supply or a 500 W power supply when running in SLI configuration.
• PCI Express x16 bus.
• GeForce 7800 GTX runs at 430 MHz with 256 MB 256-bit GDDR3 memory running at 1.2 GHz and a suggested retail price in the US of USD 599.
• Cheaper models based on the same core will probably be launched, but so far nVidia didn't announce their names or specs.

Let's now see in depth how this new chip works.