You wrote:
> To me it seems to be in order of likelihood:

> 1.    bad or not properly seated memory card
This could be because of bad seating, or because the memory slot is bad.
Did you try using the RAM in different slots?

> 2.    bad motherboard
Possible bad memory slots, or (if it is a Jumper board), maybe certain settings
can be changed to make it work.

 > 3.    bad processor (AMD K6-2 450MHz)
This depends on whether it worked with the older RAM or not.

> 4.    bad memory
This is always possible.


Did it work at all with the older RAM configuration?
If that is the case, there is the possibility that the motherboard does not
work properly with memory lareger than 64MB a piece.  The memory slot can be
defective, and so could the RAM.  If you try the older 64 MB ram chips, and it
doesn't work (if it ever did), then the mother board could have been damaged
when seating the RAM module (older boards can get brittle due to heat).  Check
the seating of all of the cards.

There is a whole other issue to put to words here also.  Since you recently
built the system, you might want to check out whether or not any soldering on
the motherboard is touching the case, it won't start either.  I have a good
example of this.  I had an older system, and it would lock up after have been
on for a while.  I would turn it off, and back on, and it wouldn't come up at
all, barely getting past the POST test.  I would turn it off for a while, and
come back.  It would boot up fine, and stay on for a while before crashing.  I
found out that it would stop functioning because of the heat.  The heat
generated would expand the motherboard, and soldering would touch the case.  I
determined this after I re-assembled the computer, and it would run for ever -
until I moved it.  After moving it, the same problem would occur.  I would
re-assemble it and it would work fine again.  One would think that it was
because of loose screws, but all were tight.  The case was rather warped, and
things did not always come together easy.

If all else fails, have the RAM tested somewhere, and if need be, get a new
motherboard that likes the new RAM and accepts the old RAM, so you get twice as
much memory.

Good luck.


-- 
Rick Rosinski
http://www.rickrosinski.com
rick@rickrosinski.com