The ATI VGA driver is a 256-colour, 16-colour and monochrome driver for XFree86. The driver is intended for all ATI video adapters except those that do not provide SuperVGA functionality (such as some early Mach8 and Mach32 adapters). The following approximate maximum resolutions (based on the Golden Ratio of x/y = (1 + sqrt(5))/2) are possible depending on the video memory available on the adapter (and the capabilities of your monitor):
256k 640x409x256 896x585x16
512k 896x585x256 1280x819x16
1M 1280x819x256 1824x1149x16
Maximum monochrome resolutions are the same as those for 16-colour mode,
because the monochrome server uses a maximum of one fourth of the available
video memory.