The STOP 0xa BSOD you get on a reboot is a generic memory corruption error. Since you've made so few changes and the BSOD occurs at reboot on a warm system, I believe it is more likely your issue is caused by a hardware problem rather than software.
1) You could test your memory more vigorously with memtest86+, running at least 3 passes.
2) Run CHKDSK C: /F /R from an elevated Command Prompt (right-click on the Command Prompt icon and choose "Run as administrator" from the popup menu, then enter the command) to confirm your filesystem is sound
3) Boot front a Linux "LiveCD" distribution or Perform an F9 ASUS Factory Restore.
How long have you had your laptop? If the above fails, you should contact your retailer and exchange your defective laptop for a new one, if you are still in the retailer's exchange/return period.
G74SX-A1 - stock hardware - BIOS 202 - 2nd Monitor VISIO VF551XVT