BSOD random times after or before playing games

Welcome to the forum.

Norton is a known cause of BSOd'. Please remove it for testing purpose. Use Microsoft Security Essentials.

Recommended from a strict BSOD perspective, compatibility & stability compared to other security software:

Microsoft Security Essentials - Free Antivirus for Windows

Malwarebytes - Free

Good and Free system security combination.

Scan with Kaspersky TDSSKiller:Anti-rootkit utility TDSSKiller

ESET online scanner: Free Online Virus Scanner | ESET

Run a System file check (SFC): SFC /SCANNOW Command - System File Checker

Install all updates including Service Pack One: Learn how to install Windows 7 Service Pack 1 (SP1)

Reduce items at start-up: Startup Programs - Change

Perform a clean boot: Troubleshoot Application Conflicts by Performing a Clean Startup

Run Disk Check on your Hard Drive(s): Disk Check

Check for heating issues using Speccy or HWmonitor

Upload a screen shot: Screenshots and Files - Upload and Post in Seven Forums

Please update these older drivers. Links are included to assist in looking up the source of the drivers. If unable to find an update, please remove (un-install) the program responsible for that driver. DO NOT manually delete/rename the driver as it may make the system unbootable!:-

nusb3hub.sys Fri Dec 10 10:50:35 2010 (4D01B19B)
NEC Electronics USB 3.0 Host Controller Driver (previous BSOD issues with 2010 and earlier versions)
Driver Reference Table - nusb3hub.sys

nusb3xhc.sys Fri Dec 10 10:50:35 2010 (4D01B19B)
NEC Electronics USB 3.0 Host Controller Driver (previous BSOD issues with 2010 and earlier versions)
Driver Reference Table - nusb3xhc.sys

Perform a clean install of a driver following: How to Clean Left Over Driver Files with Driver Sweeper

Use Revo Uninstaller to uninstall stubborn software. Opt for Advance Mode while uninstalling which allows leftover registry removal:Download Revo Uninstaller Freeware - Free and Full Download - Uninstall software, remove programs, solve uninstall problems

Keep us posted.

Code:

Built by: 7600.16988.amd64fre.win7_gdr.120401-1505
Debug session time: Tue Feb 11 23:39:44.548 2014 (UTC + 6:00)
System Uptime: 0 days 2:20:26.078
BugCheck 3B, {c0000005, fffff80002e89c6e, fffff880028e2e00, 0}
Probably caused by : ntkrnlmp.exe ( nt!ExEnterCriticalRegionAndAcquireFastMutexUnsafe+26 )
BUGCHECK_STR:  0x3B
PROCESS_NAME:  League of Lege
¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨``
Built by: 7600.16988.amd64fre.win7_gdr.120401-1505
Debug session time: Tue Feb 11 11:31:08.129 2014 (UTC + 6:00)
System Uptime: 0 days 0:54:03.659
BugCheck D1, {18, 2, 1, fffff88006869d16}
*** 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+18d16 )
BUGCHECK_STR:  0xD1
PROCESS_NAME:  System
¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨``
Built by: 7600.16988.amd64fre.win7_gdr.120401-1505
Debug session time: Tue Feb 11 10:29:48.543 2014 (UTC + 6:00)
System Uptime: 0 days 14:51:39.500
BugCheck 3B, {c0000005, fffff96000126483, fffff88006462030, 0}
*** WARNING: Unable to verify timestamp for win32k.sys
*** ERROR: Module load completed but symbols could not be loaded for win32k.sys
Probably caused by : win32k.sys ( win32k!HmgLockEx+a3 )
BUGCHECK_STR:  0x3B
PROCESS_NAME:  dwm.exe
¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨``
Built by: 7600.16988.amd64fre.win7_gdr.120401-1505
Debug session time: Mon Feb 10 19:37:41.427 2014 (UTC + 6:00)
System Uptime: 0 days 0:12:11.582
BugCheck 3B, {c0000005, fffff960007a6d15, fffff880057990e0, 0}
Probably caused by : cdd.dll ( cdd+6d15 )
BUGCHECK_STR:  0x3B
PROCESS_NAME:  dwm.exe
¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨``
Built by: 7600.16988.amd64fre.win7_gdr.120401-1505
Debug session time: Mon Feb 10 11:29:46.178 2014 (UTC + 6:00)
System Uptime: 0 days 4:16:30.708
BugCheck 50, {fffff900c2491a60, 0, fffff960001f4255, 0}
Probably caused by : cdd.dll ( cdd+2566 )
BUGCHECK_STR:  0x50
PROCESS_NAME:  League of Lege
¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨``
Built by: 7600.16988.amd64fre.win7_gdr.120401-1505
Debug session time: Mon Feb 10 06:49:10.764 2014 (UTC + 6:00)
System Uptime: 0 days 8:54:35.294
BugCheck 3B, {c0000005, fffff960000f6483, fffff880080eb030, 0}
Probably caused by : win32k.sys ( win32k!HmgLockEx+a3 )
BUGCHECK_STR:  0x3B
PROCESS_NAME:  dwm.exe
¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨``