No .. not all A3k's were softkick. Mine was but
I installed the 3.1 roms for a hardkick.
But I beleave the kickstart is still copied over
into ram.I had to go to the burned in roms in order
to run the WarpEngine. I got my info from an Aussie
from down under ;-) He told me what I needed to do
to get it going and I'm sure that is where I got that
info on the jumper. It either involved the Rom chips
or maybe the CIA chips, most likely the Roms.
If the machine tried to boot too fast the boots would
be unreliable. As I remember it, it was on a per machine
basis, meaning that each machine could be different as to
the speed of the jumper setting.
I wish I could remember more about this, I lost a Harddrive
a few months ago and that info was on it.
Its worth checking into, as it sounds like your problem.