Am 02.08.20 um 03:49 schrieb tho...@antispam.ham:
> I've not yet noticed any pattern to the random reboots. The machine
> can be up for many days when it decides to just stop without any kind
> of error message and reboot. However, by far the most frequent
> occurrence of a failure is associated with the reboot process itself,
> specifically when the white square and OS/2 appear in the upper left
> corner of the screen. If it gets past that point, the system can
> remain up for days at a time, but I've seen the system reboot process
> interrupted at that particular point many consecutive times. Could
> be an ambient temperature issue, with some component having become
> particularly sensitive to overheating.
>
> This much I can say. The Adaptec 29160 SCSI bus scan happens just
> fine. The system can boot from a MEMTEST 3.0 bootable CD just fine
> and run tests on memory for hours without failure. Furthermore, the
> machine has error-correcting memory, and the BIOS hasn't recorded any
> events, so I'm fairly confident that the SCSI adapter and memory aren't
> the source of the problem.
Most likely you have unstable power supply. Check all electrolytic
capacitors on the main board and inside the power supply for bulges. If
one is positive it is defective. Unfortunately the opposite does not
always apply.
Whether you are able to replace this capacitor on your own is another
question. In the power supply this is quite easy. On the main board you
need soldering experience and a powerful soldering iron.
Alternatively you may replace the defective component. But do not expect
any old power supply fond somewhere to work. I had at most 3 consecutive
defective power supplies in one day.
Do not care much on the rated maximum power. It is almost never the
cause of problems. Larger power supplies will primarily consume more
power as they are less efficient at the same output.
> I have Boot Manager installed, and that always comes up just fine, so
> the Boot Manager partition appears to be okay, as is the disk controller.
> I have the operating system installed on two different partitions, both
> on the same physical disk as the Boot Manager partition. Doesn't matter
> which one I try to boot from; I get the reboot when "white square OS/2"
> appears with either, so I doubt the failure is associated with a
> particular disk partition.
Typically defective capacitors do not primarily cause problems at high
power supply. More often they cause problems at with load changes. And
the first major load change is when the kernel activates power saving
states of CPU. The BIOS of older hardware usually doesn't do so.
> Does anybody familiar with the details of the OS/2 boot process know
> exactly what is happening immediately after the "white square OS/2"
> appears? Narrowing down the list of possible failing components is
> the goal here.
You know Alt-F2? It will show you the drivers loaded.
But it is not too likely that it will help you much to diagnose hardware
problems. Almost any driver may fail because of this. You will just
blame the first one that executes some code that can no longer be
executed correctly.
Marcel