Hi, My pc, Lenovo M55e, breaksdown with the following blue screen error message: *** Hardware Malfunction Call your hardware vendor for support NMI: Parity check / Memory parity error *The system has halted* The error occurs o n l y in when I try to connect some USB items, an LG external DVD drive or an external WD HD packed in an external enclosure. I checked my memory cards by replacing them, and they are flawless. In addition, I have ran a "Repair" installation of a clean streamlined SP3 disk. The disk was prepared by integrating an MS final version SP3 file with my original SP2 disk. I can connect successfully some USB items, my Nokia cellular or my Brother printer, for example. The final version SP3 was installed above some beta versions of SP3, which caused no problems. Since SP3 has been installed on my system for quite a long time, whether as beta or final, removal of it and returning to SP2 would be costful. What can be done to solve this problem.