I recently built a new desktop system and chose an Asus P8P67 motherboard. After getting the system up and running, I noticed that it would intermittently freeze – perhaps the most enraging thing that can happen when setting up a brand new machine. Checking and replacing the usual suspect hardware yielded no results, but the Internet came to my rescue and helped get things stable.
In summary, if you have a P8P67 motherboard (this should apply to all variants, including the Pro and Deluxe), try manually clocking the RAM to 1066MHz if you are experiencing freezes. My memory is rated for 1333MHz but just would not operate properly on the board at this speed. The stalls manifest intermittently; they will happen anywhere from two minutes to ten hours after boot. The display stays on, but peripherals don’t respond – this fix won’t work if your end result is a blue screen of death. Your Memtest results should also show no errors.
Later suggestions include setting the memory speed configuration to XMP, not AUTO – I haven’t tried this yet as I’d rather not jinx my current functional setup.