Ensure you have all the latest drivers installed on your HDD, including the chipset drivers. BSoDs Are usually due to driver conflicts or are sometimes Hardware problems, which can be known by the BSoD code.
Download Bluescreenview, it will show you exactly which driver is causing the problem and the date and time of the event. Scan your PC for viruses etc. Re-assemble your PC if you can.
And please give more details like which OS, and other details like model names etc