i'm using the vanilla P8P67 mobo, and yes it has the cold boot issue.
what i found out was the display card that i used, i using the pci-e power cable that provide by my power supply and the mobo will have issue.
change the pci-e power to molex type (convert molex to pci-e) , the issue gone.
maybe the pci-e lane of this P8P67 mobo is weak or whatever.....