BSOD occuring weekly

• Replace your current AV with Microsoft Security Essentials & the Free version of Malwarebytes, update and make full scans separately:
  
  • Uninstallers (removal tools) for common antivirus software - ESET Knowledgebase
  • Help protect your PC with Microsoft Security Essentials
  • Malwarebytes Free

   Note

Do not start the trial version of MalwareBytes

• Also take a look at: Good & Free System Security Combination

• Virus Check:
  
  • Make scans with these tools below:
    
    • TDSSKiller Rootkit Removal Utility Free Download | Kaspersky Lab US
    • Online Virus Scanner Eset
• Application conflict:
  
  • Reduce the start-up items. This will help avoid software conflicts:
    
    • Remove Startup Programs in Windows 7
    • Clean Startup in Windows 7

• System File Checker
  
  • The SFC /SCANNOW Command - System File Checker scans the integrity of all protected Windows 7 system files and replaces incorrect corrupted, changed/modified, or damaged versions with the correct versions if possible. If you have modified your system files as in theming explorer/system files, running sfc /scannow will revert the system files to it's default state.
    
    • Link to full tutorial: SFC /SCANNOW Command - System File Checker
• Run Disk Check in Windows 7
  
  • Run this on your Hard Drive(s). This will show you how to run Check Disk or chkdsk in Windows 7 to check a selected hard disk for file system errors and bad sectors on it. With both boxes checked for all HDDs and with Automatically fix file system errors. Post back your logs for the checks after finding them using Check Disk (chkdsk) - Read Event Viewer Log
    
    • Link to full tutorial: Disk Check

• Use Crystal Disk Info to upload a screenshot of your Hard Drives (s).
  
  • Then test your Hard Drives (s) running a Hard Drive Diag.

• Check for heating issues using Speccy or HWmonitor
  
  • HWMonitor CPUID - System & hardware benchmark, monitoring, reporting
  • Speccy - System Information - Free Download
    
    • Please upload a summary tab using Speccy. Screenshots and Files - Upload and Post in Seven Forums

• Test and Diagnose RAM issues with MEMTEST86+
  
  • Pay close attention to Part 3 of the tutorial "If you have errors". Take the test for at least 7-10 passes. It may take up to 22 passes to find problems.
    
    • Make sure to run it once after the system has been on for a few hours and is warm, and then also run it again when the system has been off for a few hours and is cold. RAM - Test with Memtest86+