I definately know it isn't an overheating problem, and i don't use mobo mon 5 because it's just extra services/clutter etc, that i can do without...
No, it hasn't happened for about ten days now... I've had a similar problem before, but the error's used to occur so quickly, that no error log was created...
When i used the onboard-sound - the CD audio plug was interfering with the seating of the video-card, and it actually used to come loose, and create the 8-3-8 beep Error codes at boot-up... Then i'd press the card with my thumb, and up she booted again.
In the end, i shaved a little plastic from the CD audio cable for extra clearance...
However, i got a 5.1 C-Media PCI card now, so the onboard's disabled, and the cable is no longer plugged into there anymore!