5.3-release fine with 512MB RAM, reboots at times with 1.5GB (but no panic)

[Jean Lagarde]

Thanks to all who replied. So it seems the consensus is a likely 
hardware issue, and I am leaning that way as well now. I will try the 
suggestion about disabling ACPI however.

To address some of the other comments, that exact CPU-mobo-memory 
configuration worked fine running Win2000 for many years, so I doubt it 
is the problem per se. Also, I did try the 1GB stick alone yesterday and 
it had similar symptoms as for 1.5 GB.

I do know where to look for a panic message and there is none.

About my running Win2000 on this hardware before, I would initially have 
thought that this made a hardware problem improbable, but I used to run 
the computer continually and I guess it's not impossible that there was 
a hardware degradation that was mitigated by the system staying warm all 
the time. The system was mothballed for a few months before my FreeBSD 
install, so the prolonged period at room temperature may have allowed 
some motherboard degradation to get worse. I was led to form that 
hypothesis because I noticed yesterday that there seems to be a relation 
with temperature: I ran burnP6 and crashme concurrently (both ran 
without problem with any memory configuration but I realize that neither 
of these two utilities necessarily stress the system in the way I need) 
and since they ran fine with the 1.5 GB in I tried to start KDE again 
(leaving the stress applications running) and it did bring everything up 
without rebooting. I stopped the system and let it cool down and KDE 
made the system reboot as before after a restart. I guess my next step 
will be to install chm or something like that to monitor the 
temperatures as the system runs, but anyway, it seems this is likely not 
a FreeBSD problem anymore, so I thank you all again for the suggestions 
and will continue troubleshooting the hardware. My immediate guess is 
either the CPU or motherboard.

Oh yeah, I still wonder thought why "memtest all" only seemed to "find" 
512MB of RAM, but I think it is a side issue at this time.

Cheers,

Jean