mike@hpfclp.SDE.HP.COM (Michael Bishop) (09/07/88)
I'm having a serious problem with my Dell Model 310 computer system which I
have not been able to solve so far. I thought I would share my experiences,
then solicit ideas and comments from the net. Perhaps others have had
similar problems. I've owned the system for about 6 weeks now.
First the machine:
Original Configuration:
20 Mhz 386 (AT Compatible)
1 MB main memory
VGA Color Plus Monitor
40 MB Hard Disk
40 MB Tape Backup
101 Key Enhanced Keyboard
I Added:
1 MB RAM (bought from Dell)
Microsoft Bus Mouse w/ mouse driver 6.24
The symptoms:
The system crashes periodically. However, there isn't a simple set of
commands, or keystrokes, or mouse movements that produces the failure
every time. The problem appears intermittently. I know it has crashed
when it refuses to accept input and the input buffer overflows. I've had
it crash with MicroSoft Word 4.0, MS Windows 386, Leisure Suite Larry (a
game), and other programs, so I do not think the problem lies in the
software I'm running. Sometimes I can soft re-boot, other times I'm
forced to cold start the machine.
What I've done so far:
At first I thought that the problem was either software related or
configuration related. It seems that the system only crashes when I'm
generating input from the mouse or keyboard. I can run a simple graphics
program (output only) for days without the system crashing. However, when
I'm using MicroSoft Word and heavily using the mouse and keyboard, the
system crashes regularly.
I called MicroSoft and told them what was going on. They seemed to think
that my problem was due to an "old" mouse driver. I was running the 6.11
version of the mouse driver. They sent me a new mouse driver (6.24). I
tried it out, quickly making the system crash again.
The next thing I tried was powering up the system without the mouse
hardware and without installing a mouse driver. I was still able to crash
MS Word quickly by just using the arrow keys to drive around in a file. I
could crash Word in about a minute or less.
Then I suspected possible BIOS bugs. The Dell Model 310 allows you to run
the BIOS in RAM for faster speed, but if that RAM was getting clobbered
inadvertently, I figured it could crash the system. So I turned the Fast
BIOS and Fast Video modes off so that I could run all of the firmware out
of ROM. The system still crashed. Finally, I turned the system speed
down from 20 Mhz to 8 Mhz. A-ha! The problem went away. I could not
crash the system at 8 Mhz.
Suspecting the hardware more and more, I called Dell Computer. I
explained the problem; They, of course, had never heard of any problems
like mine, but being the good guys that they are, they sent me a new
motherboard. A service man came out and transferred my additional 1 MB of
RAM from the old motherboard to the new motherboard. Then he installed
the new motherboard and powered up the system. It seemed to run just
fine. All of the techniques and methods that I was using to make the
system crash (at 20 Mhz) had no effect. I was somewhat confident that
that the problem was fixed. (Of course the real test would be making it
through an 8-hour Word session without the system dying.) The service man
left taking my old motherboard with him.
Well, to make a very long story somewhat shorter, I crashed Word again
about an hour into a session. It seems that the system still crashes, but
far more *infrequently* than before. So far, I've only been able to crash
the system once; the symptoms, however, are the same. Input locks up and
I'm forced to re-boot. (BTW, I've tried using Word's CNTL-ALT-/ command
to clear the input buffer, this has no effect as far as unfreezing the
system. I've also tried running Word in Text Mode, but it still crashes.)
My next experiment is to pull the 1 MB of additional RAM and see if I can
crash the system as *originally* configured. This is rather risky because
of static electricity and such.
BTW, all of the computer diagnostics (e.g., the Dell System Analyzer) say
the system is A-okay, including the RAM test.
Prognosis:
I'm tempted to call Dell and have them ship me a whole new system, but I'd
really like to know what's wrong with the one I've got. If I had to take
a guess, I'd say with fair confidence that it's a hardware timing-related
problem, and that the new motherboard solved it a little bit, but not
completely. Another possibility is defective SIMMs (memory) but it seems
that would have produced a similar failing frequency on both motherboards.
So I think the "bad memory theory" is somewhat less likely than the "bad
system timing" theory. Isn't this fun?
Does anyone have a "reasonable" suggestion for helping me to isolate and
solve this problem? I've had the computer for over a month now but have
not been able to use it very much because of these problems.
Thanks for all of your ideas.**
Michael Bishop
Hewlett-Packard/Graphics Technology Division
Ft Collins, CO.
UUCP: {ihnp4,hplabs}!hpfcla!mike-b
Internet: mike%hpfclp@hplabs.HP.COM
** Related to this topic :-).kevinc@auvax.UUCP (Kevin "auric" Crocker) (09/22/88)
In article <6640011@hpfclp.SDE.HP.COM>, mike@hpfclp.SDE.HP.COM (Michael Bishop) writes: > I'm having a serious problem with my Dell Model 310 computer system which I > Original Configuration: > 20 Mhz 386 (AT Compatible) > 1 MB main memory > VGA Color Plus Monitor > 40 MB Hard Disk > 40 MB Tape Backup > 101 Key Enhanced Keyboard > > I Added: > 1 MB RAM (bought from Dell) > Microsoft Bus Mouse w/ mouse driver 6.24 > >Michael Bishop Without trying to point the finger, we had a microsoft bus mouse her and we tried it on an AT and a 386 and everything just kept on crashing. Were pretty sure that either something was wrong with the mouse itself ( ie. it did not process signals properly) or it had something to do with the driver that processed the signals from the mouse. When we took the mouse out both machines worked perfectly. We did call microsoft and they in all fairness tried to help but nothing seemed to solve the problem in its entireity. We eventually sent it back and bought a Mouse Systems Mouse that was compatible with MS mouse as this is what we needed to run one particular piece of software. Hope this helps but I'm not too sure htat it will