Throughout the day, my Windows 7 desktop system is shutting down without warning every 2-6 hours or so. The frequency seems to be getting greater, but I'm not yet completely sure of that fact. This is the third day that this has been recurring. I replaced the motherboard (to: Asus Sabertooth 990FX) and CPU (to: AMD 8 core) about 1 month ago due to a fried chip on the previously 4 year old motherboard. The PSU is a 4 year old Corsair HX750w. During the past 4 years, I've never had a hardware issue other than the fried motherboard. I'm running a low power single slot graphics card, due to no onboard video, and don't currently play games. I don't think that too much power consumption is an issue absent the possibility of a PSU issue.
My CPU temp hovers at a steady average of about 42C. The mainboard is at 35C, the fans are running without issue, and the voltages are as follows: +3.3v = 3.147V; +5V = 4.974V; +12V = 12.055V. I have low latency (cas 7), low voltage G.Skill RAM installed that is not on the Motherboard approved list (carried over from my last setup). However, the motherboard seemed to instantly adjust and just runs the 8 Gb of RAM at different timings and voltages (1.5v vs 1.3v) than the RAM has the optimum potential for. It hasn't been a problem thusfar, and in actuality the updated hardware gives me better RAM performance (operations per second) than did the previous equipment according to the windows experience index.
It doesn't automatically reboot after it shuts down, and it doesn't restart when I press the power button. It does restart after I tilt the case slightly and then press the power button. Every time this happens, I need to tilt the case slightly and then it starts right back up. Today, for the first time, it restarted after I merely titled the case slightly without pressing the power button.
This seems to be a strange set of symptoms, and I thank anyone ahead of time who may have any insight into this.