ELSA GLoria II Quadro SDR

SPEC’s Glperf 3.1.2 is a good, low level, easy to use OpenGL test tool that one can use to look at how graphics card/systems handle specific OpenGL functions.  This tool was used to investigate the tri-meshed strip performance of the cards under review.  Tri-meshed strips are one of the most efficient ways of presenting geometric data to be processed in that it reduces the compute load for either the GPU or host CPU depending on the card’s design.  GLperf is driven by a script and the execute fragment for the one used for initial test was:

TriangleStripTest {

(UserString printf("(%s,flat)",
                  ExecuteMode))
(ExecuteMode Immediate)
(DepthTest GL_LEQUAL)
(ObjsPerBeginEnd    4)
(Size from 1 to 512 step 100%)
(ShadeModel GL_FLAT)

}

This test script generates and plots flat shaded triangle strips with the triangle areas stepping from 1 pixel to 512 pixels. The test output was put into chart form:

This chart shows triangle performance (triangles per sec.) as a function of pixels per triangle. The two main constraints on card performance is evident in the plot’s shape.  A card’s peak geometry T&L rate defines a horizontal line and the card’s peak fill rate locates the diagonal line representing constant maximum fill rate.  On the flat horizontal portion of the curve the card is triangle rate limited and on the sloped portion of the curve it is fill rate limited.

The GLoria II (Quadro) with the ELSA driver and the CL Annihilator (GeForce) with the NVIDIA 3.65 driver have almost exactly the same performance and are considerably better than any of the other cards.  The AGP version of the GVX1 is better than the PCI version.  Since the VX1 and the TNT2Ultra use the host CPU for T&L, their peak triangle rates were about the same.  The value of an on card GPU is clearly seen in this chart: the GVX1, GeForce and Quadro are clearly faster on peak triangle rate than the other cards that depend on the host CPU.

Notice that for the best of the lot (Quadro and GeForce), the peak triangle rate was only about 9 million triangles per second and the effective fill rate for simple flat shading was about 100 million pixels per second.  Welcome to the real world - so much for the PR materials.