We chose the Athlon 650MHz, Pentium III 600 MHz and a Celeron 300A overclocked to 450MHz for our CPU scaling trials. First and foremost, we wanted to see just how CPU dependant the GeForce 256 is. It's obviously no surprise that the 'faster' the CPU, the faster the resultant fps achievable but it was refreshing to see how well it scaled all the way down to a Celeron 450MHz. The TNT2's architecture was far more CPU dependant and it's safe to say that with a lower frequency CPU, you'll be in safe hands with a GeForce 256. Here are charts and graphs with the same information represented two different ways.
Besides the obvious trendline convergence at 1600 x 1200, signaling a very high (over 60 fps across the board in Quake 3 SEHQ) end of the line for fillrate performance, there are a few interesting bobbles.