We found a device, and then claimed we couldn't find one due to a
silly thinko.

agpgart: Detected AMD 8151 AGP Bridge rev B2
agpgart: Maximum main memory to use for agp memory: 816M
agpgart: AGP aperture is 64M @ 0xe0000000
No supported AGP bridge found.
You can try agp_try_unsupported=1