however the newest beta drivers don't always correctly detect your monitor. so it could be that your refresh rate is limited to 75Hz, which is pretty unworkable with the newest monitors.
latest official driver is version 6.50, but already from december 2000, i believe. it's about time they release a new one. perhaps you can get a newer one from your video card manufacturer. i mean, 6.50 doesn't support geforce 3 and some other cards, so there have to be newer official drivers somewhere...