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miod > machineroom > manufacturers > Hewlett-Packard > HP 9000/425e

HP 9000/425e

The HP 9000/425e is quite an odd machine.
Intended as a last m68k-based workstation until customers were ready to switch to the PA-RISC family, it is a cross between three machines: the motherboard is a mixture of Apollo and Hewlett-Packard 9000/300 family components (as are all members of the 400 family), using 9000/700 family case and memory...
I would dare say this machine looks like an Apollo 2500 motherboard fitted in an HP 9000/705 chassis, but this would be taking too many shortcuts... and not quite right. Just like the Apollo 2500 indeed, this machine comes in a compact case, and fits anywhere on a desk. Despite lacking expansion capabilities (since there are no expansion slots), this is nevertheless a versatile machine, using industry standard parity memory SIMMs, and the only pre-PA-RISC system to use a regular HD15 VGA connector for video output. This is also the only such machine with digital audio capabilities.


(Click on the pictures to get larger resolution images)
This machine comes in a small pizzabox case, which was reused from the successful HP 9000/700RX X terminal, as well as the HP 9000/705 and HP 9000/710 early PA-RISC workstations.
It has room for two internal storage devices, of which the rightmost one can be a removable device (either a floppy, tape, or CD-ROM drive), using a different front bezel.
By removing two screws in the back, the top, as well as a side, of the case can be removed to expose the internals.
According to the documentation, there is supposed to be a so-called ``support brace'' going from the power supply to the right edge of the case, to improve case rigidity. One can even notice the two protruding notches where it is supposed to latch. There wasn't any when I got this machine, it might have been lost.
The motherboard lies at the bottom of the chassis, with a support tray for the storage devices in the front of the case.
When I got this machine, there were no disks in it (not even the internal SCSI cable!), therefore I do not have the appropriate disk brackets. After experimenting with different ways of mounting a disk inside, I ended up reusing a Sun UltraSPARC 5 disk bracket.
Here is how the machine looks with the disk drive removed; this is not too different from how I got the machine in 2003. You might be able to notice that the motherboard power connector goes through a hole in the storage tray; it is thus necessary to unplug the motherboard to be able to remove the tray from the chassis.
And here is the unobscured motherboard. Nothing special to see, but now is a good time to rant about the internal SCSI cable: the internal connector is actually wired in an inverted position, which means that the canonical cable guides (two notches on the sides, and a small bulge in the center) need to be matched on the other side, in order to get proper SCSI operation.
Here is a better view of the motherboard, with all the connectors removed. As mentioned earlier, there are no expansion connectors on this machine; everything comes built-in: 6 memory slots, to be set in pairs, allowing up to 48MB of memory (SIMMs larger than 8MB do not work), SCSI, on-board high resolution frame buffer, 3 serial ports, one parallel port, 8-bit audio, Ethernet, and HIL and Domain keyboard connectors.
Here is a better view of the motherboard, without memory and the extra connectors riser. I even removed the processor heatsink in this picture.
Here is a better look at the riser.
To complete this tour, let's have a peek at the rear of the machine. The connectors are:


The HP Museum owns a similar machine.
Link to the museum page for this machine. From there, the DomainOS flavour owner's guide can be downloaded.


OpenBSD runs nicely on the 425e. All on-board devices, but the parallel port, are supported. There is currently no X server for the on-board frame buffer, though.
Here is a recent dmesg of my 425e:
OpenBSD 5.0-current (GENERIC) #185: Sat Dec 24 23:29:52 GMT 2011
HP 9000/425e (25MHz MC68040 CPU+MMU+FPU, 4k on-chip physical I/D caches)
real mem = 50331648 (48MB)
avail mem = 45207552 (43MB)
Parity detection enabled
mainbus0 at root
intio0 at mainbus0
frodo0 at intio0 addr 0x41c000 ipl 5: service mode enabled
dnkbd0 at frodo0 offset 0x0: no keyboard
apci0 at frodo0 offset 0x20: console, no fifo
apci1 at frodo0 offset 0x40: no fifo
apci2 at frodo0 offset 0x60: no fifo
hil0 at intio0 addr 0x428000 ipl 1
dio0 at mainbus0: 98620C, 2 channels, 32 bit DMA
arcofi0 at dio0 scode 8 ipl 6
audio0 at arcofi0
internal parallel at dio0 scode 12 not configured
spc0 at dio0 scode 14 ipl 4: 98265A SCSI, 32-bit DMA
scsibus0 at spc0: 8 targets, initiator 7
sd0 at scsibus0 targ 3 lun 0: <IBM, DCAS-34330, S65A> SCSI2 0/direct fixed serial.IBM_DCAS-34330_B3GV3534_
sd0: 4134MB, 512 bytes/sector, 8467200 sectors
le0 at dio0 scode 21 ipl 5: address 08:00:09:15:35:44
le0: 8 receive buffers, 2 transmit buffers
sgc0 at mainbus0
sti0 at sgc0 slot 0: rev 8.02;75, ID 0x27134C9F40A00499
sti0: EVRX, 2048x1024 frame buffer, 1280x1024x8 display
sti0: 10x20 font type 1, 40 bpc, charset 0-255
wsdisplay0 at sti0 mux 1
wsdisplay0: screen 0 added (std, vt100 emulation)
interrupt levels: bio = 4, net = 5, tty = 5
boot device: sd0
vscsi0 at root
scsibus1 at vscsi0: 256 targets
softraid0 at root
scsibus2 at softraid0: 256 targets
hilkbd0 at hil0 code 1: 109-key keyboard, layout 1f, 3 leds
wskbd0 at hilkbd0 mux 1
wskbd0: connecting to wsdisplay0
root on sd0a swap on sd0b dump on sd0b