oops, I actually forgot to attach the log
Anyways, here's as far as I got(with amd64.org patches):
Status: Enabled
Driver: AGPGART
AGP Rate: 8x
Fast Writes: Enabled
SBA: Enabled
Using NvAGP "1" doesn't seem to make any difference.
Same results on glxgears/glxinfo
Maybe I just shouldn't expect too much from it?