thanks to all of you I could finally install NetBSD on my 4000/60
I Also  installed a DEC RZ25 4GB disk on my vaxstation.
I ahd to work a lot to install it in the case sicne it is a very HOT disk,
it warms up the environment around very much!
Then I isntalled snapshot with kernel version 1.5-ALPHA just overwriting
the old kernel and overwriting the distribution sets.
Everything works fine but I got this problems:

if I make a very hard and heavy compiling job like compiling 6 or 7
applications teh same time so that I Can use all the RAM Avaliable it
happend to me that the system crashed and kenel debugger started. I traced
back and I got GCC was the one which made the system crash... but this
happened to me only one time. Now what is happeniing is really very weird.
AFter a while the system is running if I make hard compilation jobs, it
happened to me 2 times that the system hangs withotu a reason, no core
dumps no kernel crash, just NOTHING is displayed on the screen.
ALSO the RESET switch on the front of the vaxstation does not work anymore
and the only way for me is to POWER-CYCLE the machinee which reboots
correctly  doing fsck. also the reste switch is hanging very weird!

Anyone of you happened before this problem of machine hanging ??
could it be a problem of overheating ??
could it be a problem due to the fact that a PIN in a SIMM socket of my
vaxstation is damaged ??
the memory test anyways shows me all the memory is OK!

and I do not think it can be overhating.
I installed the new SCSI disk at about 2 centimeters higher than the
motherboard and it has no physical touch with any part of the vaxstation
case.

well let me know if someone of you ever experienced this problem which is
very weird and  impossible to explain why it happens for me!

THANKS TO ALL!

Rick