BSOD when gaming

I'm late for work, but it looks like hardware to me.
Start with these free hardware diagnostics:

H/W Diagnostics:
Please start by running these bootable hardware diagnostics:
Memory Diagnostics (read the details at the link)
HD Diagnostic (read the details at the link)

Also, please run one of these free, independent online malware scans to ensure that your current protection hasn't been compromised: Malware (read the details at the link)

Then, if the above tests pass, I'd try these free stress tests:

FurMark download site: FurMark: VGA Stress Test, Graphics Card and GPU Stability Test, OpenGL Benchmark and GPU Temperature | oZone3D.Net
FurMark Setup:
- If you have more than one GPU, select Multi-GPU during setup
- In the Run mode box, select "Stability Test" and "Log GPU Temperature"
Click "Go" to start the test
- Run the test until the GPU temperature maxes out - or until you start having problems (whichever comes first).
- Click "Quit" to exit

Prime95 download site: Free Software - GIMPS
Prime95 Setup:
- extract the contents of the zip file to a location of your choice
- double click on the executable file
- select "Just stress testing"
- select the "Blend" test. If you've already run MemTest overnight you may want to run the "Small FFTs" test instead. (run all 3 if you find a problem and note how long it takes to error out with each)
- "Number of torture test threads to run" should equal the number of CPU's times 2 (if you're using hyperthreading).
The easiest way to figure this out is to go to Task Manager...Performance tab - and see the number of boxes under CPU Usage History
Then run the test for 6 to 24 hours - or until you get errors (whichever comes first).
This won't necessarily crash the system - but check the output in the test window for errors.
The Test selection box and the stress.txt file describes what components that the program stresses.

Two other video stress tests (may be more stressful than FurMark):
Video Memory stress Test - МИРNVIDIA / Утилиты / VMT
Artifact Locator - МИРNVIDIA / Утилиты / Artifact Locator
Sorry, but I don't read the language that this website is made in.

BSOD BUGCHECK SUMMARY

Code:

Built by: 7600.16617.amd64fre.win7_gdr.100618-1621
Debug session time: Thu Sep  2 06:41:29.704 2010 (UTC - 4:00)
System Uptime: 0 days 0:52:42.672
BugCheck 1E, {0, 0, 0, 0}
Probably caused by : ntkrnlmp.exe ( nt!KiKernelCalloutExceptionHandler+e )
BUGCHECK_STR:  0x1E_0
PROCESS_NAME:  System
¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨``
Built by: 7600.16617.amd64fre.win7_gdr.100618-1621
Debug session time: Thu Sep  2 05:47:34.038 2010 (UTC - 4:00)
System Uptime: 0 days 0:41:41.006
BugCheck A, {0, 2, 0, fffff80002cd818f}
Probably caused by : hardware ( nt!KiTimerWaitTest+6f )
BUGCHECK_STR:  0xA
PROCESS_NAME:  System
¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨``
Built by: 7600.16617.amd64fre.win7_gdr.100618-1621
Debug session time: Wed Sep  1 10:13:02.002 2010 (UTC - 4:00)
System Uptime: 0 days 0:09:46.970
BugCheck D1, {120a, d, 8, 120a}
Probably caused by : ntkrnlmp.exe ( nt!KiPageFault+260 )
PROCESS_NAME:  System
BUGCHECK_STR:  0xD1
¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨``
Built by: 7600.16617.amd64fre.win7_gdr.100618-1621
Debug session time: Wed Sep  1 10:02:11.534 2010 (UTC - 4:00)
System Uptime: 0 days 0:31:28.502
BugCheck D1, {a4a6, d, 8, a4a6}
Probably caused by : ntkrnlmp.exe ( nt!KiPageFault+260 )
PROCESS_NAME:  System
BUGCHECK_STR:  0xD1
¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨``
Built by: 7600.16617.amd64fre.win7_gdr.100618-1621
Debug session time: Wed Sep  1 09:28:47.604 2010 (UTC - 4:00)
System Uptime: 0 days 0:03:14.572
*** WARNING: Unable to verify timestamp for Unknown_Module_00000000`00000000
BugCheck A, {3b15c000, d, 1, fffff80002c94661}
Probably caused by : ntkrnlmp.exe ( nt!KeAccumulateTicks+411 )
BUGCHECK_STR:  0xA
PROCESS_NAME:  System
¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨``
Built by: 7600.16617.amd64fre.win7_gdr.100618-1621
Debug session time: Wed Sep  1 09:24:38.448 2010 (UTC - 4:00)
System Uptime: 0 days 3:28:33.416
BugCheck A, {1, d, 1, fffff80002f65de0}
Probably caused by : ntkrnlmp.exe ( nt!KiPageFault+260 )
BUGCHECK_STR:  0xA
PROCESS_NAME:  System
¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨``
Built by: 7600.16617.amd64fre.win7_gdr.100618-1621
Debug session time: Mon Aug 16 12:29:54.531 2010 (UTC - 4:00)
System Uptime: 0 days 0:13:16.499
BugCheck FC, {1cca6, 8160000000ec2847, fffff88002f8c9d0, 0}
Probably caused by : ntkrnlmp.exe ( nt! ?? ::FNODOBFM::`string'+40a25 )
BUGCHECK_STR:  0xFC
PROCESS_NAME:  System
¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨``
Built by: 7600.16617.amd64fre.win7_gdr.100618-1621
Debug session time: Mon Aug 16 11:45:14.497 2010 (UTC - 4:00)
System Uptime: 0 days 0:25:43.354
BugCheck A, {4, 2, 0, fffff800028de285}
Probably caused by : ntkrnlmp.exe ( nt!KiProcessTimerDpcTable+4d )
BUGCHECK_STR:  0xA
PROCESS_NAME:  System
¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨``
Built by: 7600.16617.amd64fre.win7_gdr.100618-1621
Debug session time: Mon Aug 16 11:17:06.675 2010 (UTC - 4:00)
System Uptime: 0 days 0:43:20.049
BugCheck A, {2f8cb29, d, 0, fffff80002894431}
Probably caused by : ntkrnlmp.exe ( nt!KiSecondaryClockInterrupt+1c1 )
BUGCHECK_STR:  0xA
PROCESS_NAME:  System
¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨``
Built by: 7600.16539.amd64fre.win7_gdr.100226-1909
Debug session time: Tue Aug 10 16:12:33.699 2010 (UTC - 4:00)
System Uptime: 0 days 1:38:26.667
BugCheck FC, {1a7fb, 8140000000401847, fffff88002f8c9d0, 0}
Probably caused by : ntkrnlmp.exe ( nt! ?? ::FNODOBFM::`string'+40a65 )
BUGCHECK_STR:  0xFC
PROCESS_NAME:  System
¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨``
*** WARNING: Unable to verify timestamp for ntoskrnl.exe
*** ERROR: Module load completed but symbols could not be loaded for ntoskrnl.exe
Built by: 7600.16539.x86fre.win7_gdr.100226-1909
Debug session time: Tue Jun 29 11:08:28.096 2010 (UTC - 4:00)
System Uptime: 0 days 0:00:18.610
*** WARNING: Unable to verify timestamp for ntoskrnl.exe
*** ERROR: Module load completed but symbols could not be loaded for ntoskrnl.exe
*** ERROR: Module load completed but symbols could not be loaded for mssmbios.sys
BUGCHECK_STR:  0x6B
¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨``