Nvidia GeForce256

Recap

Let's go over the GeForce specifications once again.
Here's the spec list:

256-bit 3D processor
Integrated geometry transform engine
Integrated dynamic lighting engine
Four-pixel rendering pipeline
480 million pixels per second fill rate
15 million triangles/s throughput
Cube-environment mapping using projective textures and vertex blending
Single-pass emboss and dot-product bump mapping
350MHz RAMDAC
2D resolution of 2048x1536 at 75Hz
AGP4X with Fast Writes
Up to 128MB RAM
OpenGL ICD for Windows98, NT4, 2000
Powerful HDTV motion compensation.
Full frame rate DVD to 1080i resolution.
Estimated Price: $300-$350

There's a disturbance in the force

While everyone was ooh-ing and ahh-ing over the GeForce screenshots and cube environment mapping demos, we were busy looking over the spec list. Okay, four pixel rendering pipeline and 480Mpixels/s… that means it has a 120MHz clock speed. Wait, where's the Mtexels/s figure?

When we first saw the GeForce specification list we noticed that the texels per second number was conspicuously missing. If the last generation of cards concentrated on the texels/s number, why did Nvidia go back to listing the pixels/s number? We guessed that if the GeForce could do 960Mtexels/s, they would have included the number in the spec sheet, and the fact that the texel number wasn't listed meant the chip could probably only do 480Mtexels/s. Eventually Nvidia disclosed that the GeForce 256 only has a 480Mtexels/s fill rate.

Cube Environment Mapping

You can use cube mapping to add reflections to objects. Imagine putting a cube around an object, and taking six 1k x 1k snapshots of the walls from inside the cube. The environment map is created with these six snapshots and it's wrapped around the object. This is a very nice looking technique, but we have to wonder if the GeForce actually has the fill rate to support it.

It's all about the triangles

The GeForce may not have the fill rate, but it does have the sustained 15 million triangles per second and the 256-bit 3D processor. Onboard T&L is the GeForce's most important feature.Games that take advantage of the extra polygons with have incredibly detailed environments and bring a new level of realism to the desktop.