I've been using Burnin Pro 5 for quite some time the 3D test used a number of balls which bounced around the 3D test window. Over a period of time the reported frame rate was reasonably consistant (say 950 to 990 FPS) and we used this to weed out slow systems.
I've just started using Burnin Pro 6 which has a different 3D graphics test. On this test there are airplanes flying around some islands over the sea. The frame rates are lower (but that's probably to be expected) BUT I see a much greater difference between min and max frame rates during the test (110 to 200FPS) as the planes pass through and round different parts of the islands.
I've tried this on several PCs with similar results.
Any ideas why?