Display turns black suddenly (quite frequently)

[flashlim]

I am having some issues after using 3 monitor on my desktop. It will turn the 3 display black and i tried to exit from the black display by pressing Ctrl + alt + delete or any other things, but no luck. The problem is, it will only turn black while i am out of ram after i receive the "not enough memory notification" (but sometimes it wont turn the display black, just the message.)

My specs :
CPU I7-4770
RAM 8gb
SSD+ SSHD 120gb + 1tb
GPU Leadtek 760 GTX OC version 2GB
3 Monitor (1920x1080,1280x1024,1280x1024)
PSU 620W Cooler Master silent pro m2
Windows 8

It worked fine with 1 monitor
I usually use Mysql, Sql server, Visual studio, Netbeans, photoshop

 

[kapitalistas]

i guess thats the psu. not enough juice.

 

[flashlim]

i guess thats the psu. not enough juice.

but it wont restart or shutdown, unplug the display dosen't help too

 

[flashlim]

by changing 3 of the connector of monitor to all dvi or hdmi (digital), then the problem disappear, seems like the problem is the graphic driver is not handle well in the digital and analog signal at the same time.