The pre 2009 version of this driver is a known BSOD cause.
Please visit this link: ASUS teK Computer Inc. -Support- Drivers and Download P7P55D LE
ASUSTeK Computer Inc. -Support- Drivers and Download P7P55D LE
Scroll down to the Utilities category, then scroll down to the "ATK0110 driver for WindowsXP/Vista/Windows 7 32&64-bit" (it's about the 12th item down).
Download and install it.
Go to C:\Windows\System32\drivers to check and make sure that the ASACPI.SYS file is date stamped from 2009 or 2010 (NOTbefore).