BSOD when running multiple applications

Welcome to the forum.

Make sure your dump logging is enabled.

1. Click Start, point to Settings, and then click Control Panel.
2. Double-click System.
3. Click the Advanced tab, and then click Settings under Startup and Recovery.
4. Check Write an even to the system log, and Automatically restart.
5. In the Write debugging information list, click Small memory dump (256k).

Location of Dumps:
C:\Windows\minidump

Uninstall Bit Defender and use MSE in its place.

Microsoft Security Essentials is recommended from a strict BSOD perspective, compatibility & stability compared to other internet security software. Malwarebytes is a great combo to MSE. They are free and lightweight.

Also uninstall your existing Antivirus software before you install MSE.

Good and Free system security combination.

   Warning

Do not start the free trial of Malware Bytes; remember to deselect that option when prompted.

Perform a Clean boot:

• Troubleshoot Application Conflicts by Performing a Clean Startup

Reduce items at start-up. No software except anti-virus is required plus doing this improves the time for logging into windows:

• How to Change, Add, or Remove Startup Programs in Windows 7

Run the System File Checker that scans the of all protected Windows 7 system files and replaces incorrect corrupted, changed/modified, or damaged versions with the correct versions if possible:

• Click on the
• Type CMD on Search
• Left click and Run as Administrator
• Type SFC /scannow

Full tutorial here:

• SFC /SCANNOW Command - System File Checker