Help needed with OpenGL for ATI Xpert 128

[Gustavus]

Both of my systems use the ATI Xpert 128 video cards with which I am satisfied since I do not have any games. In WinTune however they test at an OpenGL score of 11.9 megapixels per second. When I compare to other systems with the same card in the WinTune data base many are showing around 100 megapixels and one is showing 111 megapixels. I have downloaded and installed the latest ATI drivers. What could account for an almost 10 to 1 difference in what I am getting and what others are getting from the same card? Thanks.