5.3-RELEASE has well know problems on FreeBSD/AMD64 systems with
greater than 4GB of RAM.

In order to install on a machine with >4GB of RAM, one should either
reduce the amount of installed RAM to 4GB or less.  Or, at the loader
prompt enter:
	hw.physmem=4294967296

After the installation, if the system has >4GB of RAM, a
'/boot/loader.conf' should be created that contains:
	hw.physmem=4294967296

This >4GB issue has been fixed for the upcoming 5.4-RELEASE.
We recommend that a 5.3-STABLE snapshot be used instead of 5.3-RELEASE.
One can be found at
ftp://ftp.freebsd.org/pub/FreeBSD/snapshots/Feb_2005/5.3-STABLE-SNAP001-amd64-miniinst.iso