FWIW, I had the same thing happen to me on a clean install of
1.3 over an existing 1.2G installation on a 486DX266.  After the third
or fourth try, it Just Worked, though.  

In message <9801270140.AA08824@ampere.visgen.com>, Bruce Walker writes:
>
>My system is a 486DX4/100, 32M RAM, Vesa Local Bus Adaptec SCSI,
>500M hard disk (and Sony SCSI CD, VLB ATI video).  I have re-run
>the installation in different ways several times now.  Each time
>I get a nicely installed system, all packages on the drive, but it
>won't boot.  It simply freezes immediately after the normal BIOS
>messages. I don't get the kernel version message or the booter
>stuff; just blankness.
>
>The installation is fine otherwise because I can boot it off the
>floppy...
>
>      boot sd0a:netbsd
>
>and away she goes.  I've tried running disk afterward to reinstall
>tye boot blocks, but no dice.
>
>Did you get anywhere Sonja?
>
>Thanks!
>
>-bmw