Some of you may have been experiencing a double POST on your P8P67 series motherboard whereupon after powering on the system from a cold boot, the board will power on and then immediately reset itself before it actually POSTs and shows any display on the screen. I’ll explain the fix below and give some information about why this happens.
First, I would like to stress the importance of flashing the BIOS to the latest BIOS revision as listed on our support website, You can access the ASUS EZ Flash tool from within the UEFI (advanced options, tools) to flash the BIOS from any removable device such as a USB flash drive.
From time to time we needed to implement full resets in order to maintain stability due to the architecture of the Sandy Bridge platform. For instance, the system may require one full reset when the PCH power has been cut during S5 power state. To fix the most common additional reset (double POST when powering on from off state), enter UEFI BIOS -> go to ‘Advanced’ tab -> go down to ‘APM’, press Enter -> enable the “Power on by PCIe.” function. Then press F10 to save & exit. After save & exit, let the system boot into Windows or other OS, then perform a proper shutdown: Start button -> Shut down. You will no longer have the double POST. We will fix this in an upcoming BIOS release.