Incoming Frame Rate Diagrams
You will see that things can look a lot different to what you've seen with Expendable.
At 640x480 the picture is similar to what we saw in Expendable. The graphs are all of the same shape, but the amplitudes are shifted. TNT is scaling with CPU performance.
The picture changes completely at 1024x768. Now the graphics chip is the limiting factor, all CPUs are showing the exact same frame rate.
Again Voodoo2 SLI looks almost identical to TNT at 640x480.
The story looks different at 1024x768. The second half of the demo run is still able to scale with the CPU. If you remember the demo then you'll know that the first half is the cannon scene, where all the buildings have to be drawn all of the time, the second half is the helicopter scene, which is a lot less complex. The first half seems to push even Voodoo2 SLI to the limit, the CPUs seem to perform almost identical. The second less complex half can still show a difference between the three CPUs.
Summary Incoming Results
A game that does not require quite as much CPU power is still able to give the double Voodoo2/SLI configuration an advantage over TNT. However, we don't benefit from frame rates over 30 fps whilst we do benefit from higher resolutions. It doesn't help that Voodoo2 can reach astronomical frame rates at 1024x768, if it cannot produce any higher resolutions.