Hi,

Operating systems for PC-AT needs two booters.  One occupies
MBR.  This is common for all PC-AT operating systems.  The
other occupies each OS's partition.  This depends on each
operating system.

You said your booter didn't display any text, but boot
WinNT.  This booter is first one.  I don't understand why
NetBSD's simple booter cannot display since it displays text
only.  It's very simple.  Anyway, you can use another booter
like OS-BS or others.  If you want to reinstall this booter
again from NetBSD, you can use fdisk -B for this purpose.

After all, if you still cannot boot NetBSD from a hard
drive, the second booter may have a problem.  You can
reinstall this by using installboot command in /usr/mdec.

-- Kazushi