I have a server with a S5000Psl motherboard running Ubuntu 12.10. Once a week it crashes (black screen, no response to keyboard, no network activity, onle powercycling brings it back). There is nothing in logs and nothing in bios error log after crash. I installed openipmi and discovered this message in SEL log repeating pretty often:
One more thing that worries me, is that after powering off server gives two short sound beeps. Looks like it has something with memory, but I tried to boot it with only one memory card, and yet it still was there.