Hello Andre! I'm having the same problem as others. I have 60-70% CPU usage by DPC and Interrupts. I followed your instructions, and made the test with Win 7 SDK. I uploaded the DPC_Interrupt.zip file to Skydrive, please have a look into it. As I can see, the problem is caused by "ACPI.sys", but I don't know what to do with it. Here is the link: DPC_Interrupt I hope you can help me fix this problem, because I really want to use Windows 7, but with this CPU usage I can't. This problem does not persist in Win XP or Vista, only Win 7. Thank you in advance, Patrik.