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XT-IDE Card
Power Supply
Option Cards
Based on content by William R. Walsh
Referring to these systems as though they were related to the PS/2 Model 25
is technically incorrect. However, it's quite obvious that at least some
of the same designers worked on both (Ed. or they shared some of the design
documentation). EduQuest systems are much
bigger in size than your average Model 25.
Models 30 and 40 come with DOS 5.0 in ROM. A Setup utility is built in,
there is no reference or starter disk I know of. As with the other models, the
only way I've found to get into the BIOS setup utility is to cause an error
during the power on self test (POST). Holding down a key on the keyboard is
quite effective for this. All EduQuest models that I've worked with produce a
distinctly unhappy "beep boop" sound when a self test failure occurs, so you'll
know when you've managed to trigger an error.
I have found that use of a disk manager (those based on Ontrack software)
requires a "cooked" diskette as the EduQuest Models 30 and 40 (and possibly all
other EduQuest models) cannot boot the DR-DOS used with Ontrack's solution. Why
I don't know. Replacing the DR-DOS system with MS (or possibly even PC) DOS
might work. Whether these machines can boot FreeDOS or not is unknown.
528MB disks are the maximum supported by the on-board IDE. Higher capacity
is possible if you use a disk manager program. However, there is also a
hardware solution to using larger disks or CompactFlash cards in the
form of the XT-IDE board.
XT-IDE and the EduQuest
(This is primarily relevant to the EduQuest Models 30, 40 and others that
have DOS-in-ROM present on the motherboard. By the time of the EduQuest 55,
this seems to have been dropped.)
It is reported that when used normally, an XT-IDE adapter is not compatible
with the EduQuest as its option ROM is not allowed to load. Chris Esch
discovered
that there is a solution in the form of removing the expansion ROM that
contains the EduQuest's DOS-in-ROM functionality. From that point, the XT-IDE
adapter's ROM can be placed into the socket from which the original DOS-in-ROM
chip was removed. Be careful that you insert the chip correctly. Otherwise you
may burn it or your EduQuest system out.
Power Supply
I noticed at times of changing load, that the power supply in all of my
EduQuest systems would sometimes behave in an unstable manner. The screen image
would shrink or "vibrate" noticeably if something like an internal CD-ROM drive
were to spin up. None of them ever failed as a result of this, and I
never got so far as to diagnose it. My best guess would be faulty or dried-out
electrolytic capacitors that had changed in value, particularly any that were
being used as power filters.
Option Cards
There are some special option cards for use in the EduQuest systems. While
they are in fact normal ISA cards, the component side and connectors on the
card are flipped from their normal orientation to fit special "EduQuest slots"
in the EduQuest machines. The EduQuest machines that supported these cards also
had standard ISA connectors for use with conventional ISA expansion cards.
I'm sure there are more of these around, but all I have run into so far is
the EduQuest sound card and the Token Ring network interface card.
The following pages cover these cards and any related components in more
detail:
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