Horizontal lines on screen , not v-sync

CharizardPT

Honorable
Jan 28, 2014
4
0
10,510
Hello everyone .

When i bought my pc back in August 13' , everything was fine. I played every game normally and without using v-sync. Then , some horizontal lines appeared on screen . I took it to the store and they reinstalled windows and everything went back to normal . I played varied games from CS:GO to Battlefield 4 without problem
Two weeks ago , it started showing again. I reinstalled windows , and , for that night , the lines disappeared . But not for long , next day they were back again.

Can anyone help me?


Additional information: Turning on V-sync doesnt help
Im using a dvi to vga adapter and a vga screen.
Graphics card: Asus 650TI Boost
Only appears during games