After installing RH 6.1 from a CD (the official ISO image,
custom install) on an AMD Athlon based computer with 256 MB
RAM, I noticed that only 64 MB of it was available.
I managed to make the rest available by adding the line
to /etc/lilo.conf and reinstalling LILO with the command
'lilo'. The installer should do this automatically.
It's a known problem with some of the Athlon BIOS'es.
We're looking at ways to work around this.
Try out the latest installer available in beta. Reopen this bug if you are
still having problems.