OT: Weird Hardware Problem

Valeri Galtsev galtsev at kicp.uchicago.edu
Tue May 19 16:11:21 UTC 2020

On 5/19/20 11:01 AM, Tim Daneliuk wrote:
> On 5/19/20 10:14 AM, Michael Schuster wrote:
>> Any chance of capturing a serial console?
> Difficult.  I'm not sure it would tell me much, though.  When this happens,
> the machine just does an instantaneous hard reset as if I had hit a button
> to do so.

What if you replace power supply with new one speced twice as powerful 
as the original one? (borrow from someone for a day or two if you don't 
have one on the shelf) These things may happen when the power supply is 
marginally enough powerful for the machine. Also with age electrolytic 
capacitors are loosing capacitance, which leads to the same (both 
capacitors on AC adapter or on system board may be the culprit for 
slightly different reasons.

I would inspect system board very carefully, especially around CPU, for 
any of capacitors bulging, or any traces of capacitors leaked. Those are 
filtering ripple on PCI[-x/e,...] bus, and ripple there hitting slightly 
above some threshold will make the machine just reboot.

Please, keep us posted.



Valeri Galtsev
Sr System Administrator
Department of Astronomy and Astrophysics
Kavli Institute for Cosmological Physics
University of Chicago
Phone: 773-702-4247

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