Asus P7P-DE Pro Problem?

Dear Colleagues
Why does the blue page (dumping physical memory) randomly shows up on a PC with this configuration:
MS = Ausu P7P-DE Pro
Ram= Corsair xms 1366 (8 GB)
CPU = Intel core i5
VGA = Asus Ati 5750
Mostly seen during system shut down
Passmark Tests are OK and do not fail.
Thank you