For context: I wrote the original reboot-through-BIOS code.
For one thing, a triple fault will halt the CPU until a hardware reset
AFAIK. You won't get any further than that.
However, when the reboot-through-BIOS was originally written, we didn't
do a triple fault.
Trying the keyboard thing first, then the BIOS reboot, seemed like a
good idea. Unfortunately, I could never get it to work. The machine
would hang after the keyboard reboot bit.
When I ran similar keyboard reset code from user mode, and from DOS
debug, it didn't halt the system or have any other noticable effects.
(This is on one of those dodgy 486s that we're talking about). So I
never figured out _why_ it hung. Maybe I was tired :)
-- Jamie