Hello. Sometimes my PC suffers from high CPU usage by Interrupts My specs are: Intel Core 2 Duo E6600@2.4GHz Asus P5W DH Deluxe 2x2GB OCZ DDR2 800Mhz Asus GTX260 Windows 7 Ultimate 64 bits Three SATA hard disks (WD Caviar Green 2TB, WD VelociRaptor 1500HLFS and a Maxtor HDD) I followed the steps of the first post a here are the results: Process Explorer when CPU usage is around 30% by interrutps DPC Latency Checker running when the high cpu usage occurs Windows Performance Analyzer showing DPC and Interrupt CPU usage Summary table I've tried LatencyMon but when i press the 'Play' button the Interrupt CPU usage goes down. EDIT: Here is another summary table that confirm the results: On both cases, the CPU usage went down when cmd.exe created the 'DPC_Interrupt.etl' file Here is the DPC_Interrupt.rar file. Thanks for read me