Hey Dennis welcome my friend.
When the error happens has your CPU been powered down? Or maybe the power switched off at the socket.
What it sounds like is that the bios is retraining the ram settings each time and while your overclock might be stable (99%) the possibility exists that you are on the edge of stability with your ram.
Are you running 4 x 2GB sticks or 2 x 4GB sticks?
Could you list what your voltages are for the main settings please.
To help us help you - please provide as much information about your system and the problem as possible.