Hello and Welcome
Avast sometimes contributes in blue screens. Can you uninstall for testing purpose?:
Code:
Start Menu\Programs\avast! Free Antivirus Public:Start Menu\Programs\avast! Free Antivirus Public
Microsoft Security Essentials.
Recommended from a strict BSOD perspective, compatibility & stability compared to other antiviruses/internet security software. It is free and lightweight:-

Warning

Do not start the free trial of Malware Bytes; remember to deselect that option when prompted.
Run a full scan with both (separately) once downloaded, installed and updated.
Click on the Start

► Control Panel ► Programs ► Uninstall a program ► Uninstall everything related to "ATHEROS" and reboot the system. Delete remnants of its
drivers/older drivers using
Driver Sweeper.
Drivers - Clean Left over Files after Uninstalling
If its wireless, match your device from here:
If its not a wireless, match your device from here:
Check for an update on your video drivers. (Reinstall video drivers as mentioned in clean left over drivers tutorial)
Code:
Driver c:\windows\system32\drivers\atikmdag.sys (8.1.1.921, 5.76 MB (6,037,504 bytes), 18/08/2009 04:48)
Perform a System File Check:
- Click on the start

- Type CMD on Search
- Left click and Run as Administrator
- Type SFC /scannow
Full tutorial here:
Disk Check on your hard drive for file system errors and bad sectors on it:
Reduce items at start-up. Nothing except anti-virus is required:
BSOD Report Code:
*******************************************************************************
* *
* Bugcheck Analysis *
* *
*******************************************************************************
Use !analyze -v to get detailed debugging information.
BugCheck D1, {44, 2, 0, fffff880040da8c1}
*** WARNING: Unable to verify timestamp for athrx.sys
*** ERROR: Module load completed but symbols could not be loaded for athrx.sys
Probably caused by : athrx.sys ( athrx+5c8c1 )
Followup: MachineOwner
--------- Hope this helps.