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Poly throughput
Now let's turn attention to polygon throughput with some T&L-oriented tests.

The trend is clear: the GeForce2 Ultra is faster than the GeForce3 at T&L. Here's why: the GeForce3 chip has both its programmable vertex shader and a fixed-function T&L unit to serve legacy apps. (That's one reason the GeForce3 chip is 57 million transistors.) If a program doesn't specifically call for a vertex shader, the hard-wired T&L engine is used. In all likelihood, the fixed-function T&L engine on the GeForce3 is very similar to the same engine on the GeForce2. However, the GeForce2 Ultra runs at a higher clock speed than the GeForce3—250 versus 200MHz, respectively. Thus, the Ultra pumps out more polys in these lighting tests.

Were these true vertex shader tests, the rest of the cards might not even be able to complete them. If they did, however, they'd have to use the CPU for vertex manipulation, and performance would drop through the floor. Even 3DMark's vertex shader test doesn't use real vertex programs.

It's no great surprise that 3DMark doesn't use the vertex shaders' full capabilities. If it did, the graph above would probably have only one bar on it.