[This is i386 specific, was already in port-i386.]

There is an extended algorithm to find the size of installed
RAM in -current bootblocks (i386/stand), available with
next sup.
It should be able to detect many GBytes of memory...
If there are unexpected results or hangs, try to compile
the bootblocks with "-DCONSERVATIVE_MEMDETECT"
and report about the problem.

best regards
Matthias Drochner