Perhaps this information I found on Microsoft Technet could give you any hints:
Stop 0x00000050 or PAGE_FAULT_IN_NONPAGED_AREA
This Stop message, also known as Stop 0x50, occurs when requested data is not found in memory. The system generates a fault, which indicates that invalid system memory has been referenced. This fault can occur due to a variety of error conditions, such as bugs in antivirus software, a corrupted NTFS volume, or faulty hardware (typically related to defective RAM, be it main memory, L2 RAM cache, or video RAM).