Ok, here's what I would recommend:
(I'm assuming that is a VIA chipset board.)
First go to
www.viahardware.com and download and install the newest AGP driver. 4.05c is the newest I think. (Install in Turbo mode.)
Now go into the bios and set AGP speed to 2x. There is only an extremely minor decrease in performance by doing so. (Massive increase in stability on some systems though.) Make sure fastwrites and sidebanding are also disabled.
At this point I would also change the mip-mapping level to "high quality" rather than "best image." This can be found usually by: right click desktop > properties > settings tab > advanced button > GeForce (etc) tab > additional properties > direct 3d tab > change mip mapping level. (Note that the exact location may differ a little.)
That should take care of it.
