I had this same issue and it was memory related.
http://vip.asus.com/forum/view.aspx...&board_id=1&model=P8P67 PRO&page=10&count=124
Updated to 1204 bios.
Used XMP profile on memory.
Cold boot issue went away.
On mine it was always the memory error light staying lit. My understanding is that SB is finicky with high end memory. 1333 works best if you just want it to work. If your XMP profile runs more than 1.5v on the memory you may need to set things up manually.
http://vip.asus.com/forum/view.aspx...&board_id=1&model=P8P67 PRO&page=10&count=124
Updated to 1204 bios.
Used XMP profile on memory.
Cold boot issue went away.
On mine it was always the memory error light staying lit. My understanding is that SB is finicky with high end memory. 1333 works best if you just want it to work. If your XMP profile runs more than 1.5v on the memory you may need to set things up manually.