Sorry for the lare reply. I've been a bit busy lately.
It seems like a power management issue. Did it also happen while you were working or only when the PC was idle or asleep? You can check /var/log/dmesg (and other log files in that directory) for anything useful. I'll look into any possible issues regarding that hardware.
Other than that, it seems that sleeping support has been troublesome lately. My old Intel-based Mac Mini also has similar issues when sleeping (doesn't wake up).
Thanks for the response,
I think I've solved it, it's been up for 5 days no with no crashes. I realized that the only hardware change I made since the initial build was to add a PWM case fan. I unplugged it from the board since I didn't really need it and it is unnecessary noise. AMD makes finding actual CPU temps difficult so I had decided to be cautious.
Since then not a single crash.
Some things I've considered:
--Possibly the variable case fan speed (PWM) caused a power supply glitch at times. I haven't researched whether that is a known issue with these mobos. I hope not.
--The wires for the front switches run against that fan frame and the shutdowns were similar to a reset button push so maybe the fan motor was inducing a false reset signal or something. I sometimes see some very odd wiring/noise issues at work so it isn't too far fetched.
--Perhaps the physical button is flaky and was actually closing the circuit. I actually had never used it prior to having this issue.
--I do recall that I had some problems determining polarity (if any) of the switch wires, a few of the connectors that run from the case to mobo headers were unmarked but I assumed that those were simply momentary switches and it didn't matter.
--Maybe the PSU is bad
--It might also just be coincidence but I won't argue with success.
For the record this is my part list---I bought components thinking this would be a Windows PC, neither the motherboard nor CPU have good linux support so a hardware issue is possible.
CPU: AMD A10-7850K 3.7GHz Quad-Core Processor
CPU Cooler: Scythe BIG Shuriken 2 Rev. B 45.5 CFM Sleeve Bearing CPU Cooler
Motherboard: Gigabyte GA-F2A88XN-WIFI Mini ITX FM2+ Motherboard
Memory: Patriot Viper 3 Low Profile Red 8GB (2 x 4GB) DDR3-1866 Memory
Storage: Samsung 840 EVO 120GB 2.5" Solid State Drive
Case: Corsair 250D Mini ITX Tower Case
Power Supply: Rosewill Hive 550W 80+ Bronze Certified Semi-Modular ATX Power Supply