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Avast! antivirus is contributing in your crashes, uninstall it and replace with Microsoft Security Essentials at least to test.
Recommended antivirus program for Windows 7 based on stability compared to others:-
:warn: 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.
Update your BIOS version:
Code:
BIOS Version/Date Phoenix Technologies, LTD R01-A2, [COLOR="Red"]5/15/2008[/COLOR]
Run these tools and delete anything they find:
ESET online scanner:
Code:
fffff880`082c3478 fffff880`03bc2c0c dxgmms1!VidSchWaitForQueuedPresentLimit+0x168
fffff880`082c3480 fffffa80`01b6e2f0
fffff880`082c3488 fffff880`0fa6bab3*** WARNING: Unable to verify timestamp for nvlddmkm.sys
*** ERROR: Module load completed but symbols could not be loaded for nvlddmkm.sys
nvlddmkm+0xa5fab
The latest drivers for NVIDIA are a little problematic as I've heard. Click on the Start

rb: ► Control Panel ► Programs ► Uninstall a program ► Uninstall everything related to; NVIDIA
Reboot the system. Now delete remnants of its drivers using
Driver Fusion/Sweeper.
Reboot if required
Download and install the drivers from the link of Filehippo bellow:
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
rb:
- Type CMD on Search
- Left click and Run as Administrator
- Type SFC /scannow
Full tutorial here:
Run Disk Check on your hard disk for file system errors and bad sectors on it:
Free up the start-up, nothing except the antivirus is usually needed.
For monitoring the heat/celsius of the system, use Speccy or HWinfo:
Let us know the results.