IMO this is most likely a hardware problem with your video card (as you've updated your drivers already).
Since the system was purchased in February, it should still be under warranty.
Have you blown the vents out with canned air? (Don't use a vacuum or an air compressor as they'll damage the system)
To test your video card, please run this free stress test:
Please remove Daemon Tools as the SPTD.sys driver has been known to cause BSOD's.
BSOD BUGCHECK SUMMARY
Code:
Built by: 7600.16539.amd64fre.win7_gdr.100226-1909
Debug session time: Sun Jul 25 12:33:39.113 2010 (UTC - 4:00)
System Uptime: 0 days 3:23:30.908
*** WARNING: Unable to verify timestamp for Unknown_Module_00000000`00000000
BugCheck 1000007E, {ffffffffc0000094, fffff8800417ed85, fffff88005f2cf78, fffff88005f2c7e0}
Probably caused by : Unknown_Image ( ANALYSIS_INCONCLUSIVE )
BUGCHECK_STR: 0x7E
PROCESS_NAME: System
จจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจ
Built by: 7600.16539.amd64fre.win7_gdr.100226-1909
Debug session time: Sat Jul 24 17:40:25.987 2010 (UTC - 4:00)
System Uptime: 0 days 9:28:03.782
*** ERROR: Module load completed but symbols could not be loaded for atikmdag.sys
BugCheck 1000007E, {ffffffffc0000094, fffff880041a5d85, fffff88005ef2ee8, fffff88005ef2750}
Probably caused by : atikmdag.sys ( atikmdag+35ed85 )
BUGCHECK_STR: 0x7E
PROCESS_NAME: System
จจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจ
Built by: 7600.16539.amd64fre.win7_gdr.100226-1909
Debug session time: Tue Jul 13 08:23:43.955 2010 (UTC - 4:00)
System Uptime: 0 days 1:15:18.874
*** ERROR: Module load completed but symbols could not be loaded for atikmdag.sys
BugCheck 1000007E, {ffffffffc0000094, fffff880041b4d85, fffff88005f25ee8, fffff88005f25750}
Probably caused by : atikmdag.sys ( atikmdag+35ed85 )
BUGCHECK_STR: 0x7E
PROCESS_NAME: System
จจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจ
Built by: 7600.16539.amd64fre.win7_gdr.100226-1909
Debug session time: Mon Jul 12 20:46:07.964 2010 (UTC - 4:00)
System Uptime: 0 days 13:40:32.884
*** ERROR: Module load completed but symbols could not be loaded for atikmdag.sys
BugCheck 1000007E, {ffffffffc0000094, fffff88004212d85, fffff88005edbee8, fffff88005edb750}
Probably caused by : atikmdag.sys ( atikmdag+35ed85 )
BUGCHECK_STR: 0x7E
PROCESS_NAME: System
จจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจ
Built by: 7600.16539.amd64fre.win7_gdr.100226-1909
Debug session time: Thu Jun 17 15:10:15.156 2010 (UTC - 4:00)
System Uptime: 0 days 11:24:09.076
BugCheck A, {0, 2, 0, fffff800030d169f}
Probably caused by : dxgmms1.sys ( dxgmms1!VidMmiProcessTerminationCommand+5f )
BUGCHECK_STR: 0xA
PROCESS_NAME: System
จจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจ