Hello there!
Seems like it could be hardware most probably it could be Hard drive. I would recommend to run a hard drive Diagnostic. Check this link
Hardware Diagnostic | Captain Debugger and follow the portion about Hard drive Diagnostic.
Download Malwarebytes and run a complete scan just it be sure it's not false positive.
Update the Following Drivers:
The drivers dated 2005 should be updated or removed.
BSOD BUGCHECK SUMMARY Code:
Loading Dump File [C:\Documents and Settings\Shyam\_jcgriff2_\dbug\__Kernel__\072912-34578-01.dmp]
Built by: 7601.17835.amd64fre.win7sp1_gdr.120503-2030
Debug session time: Sun Jul 29 18:58:29.808 2012 (GMT+5)
System Uptime: 0 days 1:06:11.200
BugCheck DA, {504, fffff6fc40005fb8, 1, bf7}
Probably caused by : ntkrnlmp.exe ( nt! ?? ::FNODOBFM::`string'+b57b )
DEFAULT_BUCKET_ID: VISTA_DRIVER_FAULT
BUGCHECK_STR: 0xDA
PROCESS_NAME: System
FAILURE_BUCKET_ID: X64_0xDA_nt!_??_::FNODOBFM::_string_+b57b
Bugcheck code 000000DA
Arguments 00000000`00000504 fffff6fc`40005fb8 00000000`00000001 00000000`00000bf7
BiosVersion = 6.00 PG
BiosReleaseDate = 03/11/2010
SystemManufacturer = OEM
SystemProductName = OEM
MaxSpeed: 3200
CurrentSpeed: 3200
จจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจ``
Loading Dump File [C:\Documents and Settings\Shyam\_jcgriff2_\dbug\__Kernel__\072912-46640-01.dmp]
Built by: 7601.17835.amd64fre.win7sp1_gdr.120503-2030
Debug session time: Mon Jul 30 02:05:58.750 2012 (GMT+6)
System Uptime: 0 days 0:17:26.141
BugCheck A, {fffff6fc4005f438, 2, 0, fffff80002ed3c02}
Probably caused by : USBPORT.SYS ( USBPORT!USBPORT_Core_ProcessScatterGatherList+114 )
DEFAULT_BUCKET_ID: VISTA_DRIVER_FAULT
BUGCHECK_STR: 0xA
PROCESS_NAME: System
FAILURE_BUCKET_ID: X64_0xA_USBPORT!USBPORT_Core_ProcessScatterGatherList+114
Bugcheck code 0000000A
Arguments fffff6fc`4005f438 00000000`00000002 00000000`00000000 fffff800`02ed3c02
BiosVersion = 6.00 PG
BiosReleaseDate = 03/11/2010
SystemManufacturer = OEM
SystemProductName = OEM
MaxSpeed: 3200
CurrentSpeed: 3200
จจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจ``
Loading Dump File [C:\Documents and Settings\Shyam\_jcgriff2_\dbug\__Kernel__\072912-49578-01.dmp]
Built by: 7601.17835.amd64fre.win7sp1_gdr.120503-2030
Debug session time: Mon Jul 30 01:47:19.370 2012 (GMT+5)
System Uptime: 0 days 0:29:28.761
BugCheck A, {fffff6fc4005fa38, 2, 0, fffff80002ec7c02}
Probably caused by : memory_corruption ( nt!MiReplenishBitMap+48 )
DEFAULT_BUCKET_ID: VISTA_DRIVER_FAULT
BUGCHECK_STR: 0xA
PROCESS_NAME: explorer.exe
FAILURE_BUCKET_ID: X64_0xA_nt!MiReplenishBitMap+48
Bugcheck code 0000000A
Arguments fffff6fc`4005fa38 00000000`00000002 00000000`00000000 fffff800`02ec7c02
BiosVersion = 6.00 PG
BiosReleaseDate = 03/11/2010
SystemManufacturer = OEM
SystemProductName = OEM
MaxSpeed: 3200
CurrentSpeed: 3200
จจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจจ``