Computer is Win 7, ASUS, MB CM6850, i7-2600, Nvidia Geforce 520, Main Mon. CRT Cornerstone P1750 VGA input (VGA output from from Gefore 520 graphics card), 2nd Monitor ViewSonics VG2230wm DVI input (DVI output from from Gefore 520 graphics card), setup for extended display op. Been operating w/o problems for several months. A few days ago (no changes or new software aps. added) the VG2230wm began blanking out (blue power button on and illuminated). Replaced LCD with another LCD which is know working LCD, same issue with blanking. Tried msconfig.exe services and turning off all services except MS Services, did not resolve issue.