When turning on my pc or waking it from sleep it will intermittently fail and has been increasingly getting more frequent. It seems like a normal boot but nothing will display and it will just stay in this state until I hold down the power key, then causing it to shut down for about a second before it powers back up again automatically returning to its previous state. The reset button doesn't do anything when its in that state either.
When it does turn on it is fine until shut down, have had it on for days at a time without a problem, running benchmarks, playing games etc.
My specs are:
Motherboard: msi P67A-GD65 B3
CPU: i5-2500K 3.30GHz
RAM: G.Skill RipJawsX 2x4GB
GPU: Tried both a XFX HD 5870 and a msi GTX 680 Twin Razor
PSU: BeQuite Dark Power Pro 850w
All the current parts are under a year old with the latest firmware with the exception of the PSU which I don't remember when I got, probably over 4 years ago though.
I've tried without anything essential plugged in, including hard drives, DVD drive but it has made no difference. Also tried plugging in a speaker to see if there were any beeps but the speaker either doesn't work or there are no codes output.
Trying out both sticks of ram on their own in the first slot reduced the frequency of the failures but neither removed the problem and I haven't noticed any damaged capacitors on the motherboard.