HP/9000 425e notes
As far as I know, the 425e is the last of HP's 68K lineup.
It appeared around 1991, at about the same time as the PA-RISC based
7xx ("Snakes"). Because of this timing, I guess it was not such a big success.
It is, however, a cute little pizza box, about the size of a
712, with the
same performance as the 425t.
I obtained the machine sometime in 2004, IIRC, it was my first HP 68K box,
and it took quite some time until I figured out how to turn it into a running machine.
It came with an original monitor, so shipping costs by far outweighed
the price of the computer itself. The monitor, an A-1097 wasn't good anymore,
so I dumped it. The 425e video should work with any sync-on-green capable monitor.
The machine came rather naked, i.e. no hard disk, not even a disk carrier (and no OS of course)
and very little RAM. Unfortunately not all 50-pin SCSI disks will work,
and keep in mind the 2GB limitation for HP-UX 9.x and below.
As for RAM expansion, the 425e is rather picky,
see below, the respective modules aren't easy to spot,
they may appear once in two years on eBay.
Pixx
Battery
Exchanged 3V battery (old: Panasonic 3V BR 2325)
Memory
72-pin PS/2-style modules, but
I guess 40bit rather than 36bit parity RAM will be needed:
8MB Memory pieces from RS/6000-25T did not work
8MB Memory pieces from RS/6000-360 did work, but only 4MB recognized
Kingston: KTH425E/4/8/16; HP: A2202A
Floppy oddities
TEAC floppy: SCSI Id=0, factory default. Jumpers at the rear side, "reverse logic": all ON => Id=0.
LAN
8-fold jumper close to the LAN outlet toggles between BNC/AUI output
Last updated: 7-Jan-2012, M.Kraemer
