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NVidia introduced GeForce 3

NVidia introduced GeForce 3

Nvidia has now introduced the GeForce 3 chip with 57 million transistors. The new graphics chip from Nvidia now has as many transistors as a Pentium III and Pentium 4 combined.

A similar chip will also be used in Microsoft's X-Box. The desktop PC version has 4 rendering pipelines with two texture engines each and is operated with a chip clock of 200 MHz. Each pipeline is able to process up to 4 textures in one pass. The GeForce 3 chip is manufactured using 0.15 µm technology. However, the advantages of the new chip compared to its predecessor are only fully exploited with DirectX 8 and the corresponding software, which also makes use of the new hardware options. Then it should enable breathtaking real-time animations that were previously only possible on large render farms with a lot of computing time.

The programmable geometry unit should be particularly interesting for game programmers. It can be used to load some effects and processes using small programs (vertex shaders) for the treatment of 3D data and the lighting in the GeForce 3 (nfiniteFX architecture). Vertex shaders allow, for example, a facial expression to be changed to another expression using keyframe interpolation. In the case of water fountains, fireworks and all other pixel systems, it also calculates the trajectory, service life and brightness of the particles. Other applications include realistic deformation of skin and clothing (matrix skinning), blowing hair or fur, as well as fluttering flags (procedural deformation) and special lens effects (fish-eye). Since the vertex shaders can be loaded into the chip at any time, they can be constantly exchanged during a game.

New is also the ability to have polynomial surfaces, such as spheres, cylinders and curved surfaces, in the form of a fewControl points are passed on to the GeForce 3 and so organic shapes and large ground formations with thousands of polygons can be created without the AGP bus being blocked with huge amounts of data. Since the memory is still a limiting factor, Nvidia has also taken measures to use the memory more effectively. There is already speculation that there will soon be GeForce 3 cards with 256-bit DDR SDRAM. Among other things, this is a process with which hidden pixels are not even calculated. This appears to be a Z-test that saves texture access, but requires that the objects are transmitted to the chip sorted from front to back. ATI uses a similar process (Hyper-Z) with the Radeon cards. If objects are completely hidden behind a wall or other objects, they are not even transferred to the graphics chip.

The GeForce 3 also has improved full-scene anti-aliasing, which largely suppresses the staircase effect on sloping edges. The multisampling (Quincunx AA) of the GeForce 3 manages with fewer memory accesses than the supersampling of the GeForce 2, since it only calculates the polygons in a higher resolution, but not the textures. Even with fourfold antialiasing, the performance drop should not be more than 40 percent. With Quake3, 72 frames/s should still be possible with maximum settings below 1024x768 and 32 bit color depth with double antialiasing. The Geforce 2 Ultra manages 'only' 34 frames/s here. Now the only thing missing is programs that take advantage of all these features.

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