Instructions for modifing the config file:

Edit the <base dir>/xc/config/cf/xfree86.cf
Starting on line 436 It should read:
    #   define XF86SvgaDrivers nv et4000 et3000 pvga1 gvga r128 ati sistvga8900 \
    cirrus ncr77c22 compaq mga oak al2101 \
    ali cl64xx video7 ark mx realtek s3_savage s3v apm \
    s3_svga neo cyrix chips rendition p9x00 \
    spc8110 i740 tdfx smi generic

It defines which drivers will be put into the SVGA server.
Add "geode" and remove "cyrix" from this list.