See if this will help. It is hard to id the offending driver(s) This error occurs when you try to put the system in standby mode. The cause is a third-party driver that doesn't comply with the Advanced Configuration and Power Interface (ACPI) standard for power management. When the system goes into standby mode, it tells all drivers that the system is changing power state. If a driver doesn't respond correctly, the system displays a blue screen. Almost any kind of driver (e.g., CD-ROM drivers, network drivers, keyboard filter drivers) can cause this problem. The easiest way to fix it is to perform the following steps: 
I get this problem with my E6400. I've installed the Windows debugging tools and Symbols but I can't find the driver responsible for the problem. Has anyone had this issue withe their E6400? I get the problem when I do a shutdown to normal power-off state. sometimes if I leave the laptop it happens when it goes to sleep. I reported it to Dell Tech Support but they aren't helping, only providing a link to a generic MS website.... [URL]   ....which hasn't helped.   The Windows Problem Reports and Solution option in the control panel shows the following additional information...     BCCode: 9f BCP1: 0000000000000003 BCP2: FFFFFA8007C719B0 BCP3: FFFFFA8007CB29B0 BCP4: FFFFFA800C497240 OS Version: 6_0_6001 Service Pack: 1_0 Product: 256_1     I'm using the latest drivers available for the laptop from the Dell support site. Is there a likely or known common cause? Thanks Mike   
DRIVER_POWER_STATE_FAILURE bluescreen on Latitude E6400 Vista x64 Ultimate