Hi I am currently upgrading my computer with the following configuration CPU - intel Core i3 2100 3.10ghz SandyBridge Motherboard - intel DH67CL RAM - G.Skill DDR3 2GB x2, 1.5v, 1333mhz, Dual Channel HDD - Seagate 1TB SATA 6gb/s DVD Writer Onboard Graphics Onboard Audio Drivers - All original updated from intel.com No Overclocking, stock BIOS USB pendrive drivers USB 2.5" WD Passport for backup WinXP Pro SP3 New installation from on PC after full format, no imaging Problem PC isgiving me intermittent BSOD's with two reasons. I cannot reproduce or anticipate the BSOD, they might occur after 1hr or after 3hrs ?? PAGE_FAULT_IN_A_NON_PAGED_AREA fastfat.sys IRQL_NOT_LESS_OR_EQUAL I am at my wits end trying to understand the reason behind this. I have installed no new software, no device drivers. All external peripherals are old and well tested. I did have a hairy time moving WinXP to AHCI after installation, but it was working fine after that. I have included dump files from several events to help understand the problem. I am currently not in front of this PC, so please bear me out. What causes these BSOD's and how to remove them ??