I used OpenSuse 13.1 for a long time without any troubles(and without additional turning).
But unfortunately there is strong discomfort for eyes with Leap 42.1.

I 've tried to resolve the ussue by replacing defaul video driver with Nvidia one. No results and no ideas what to do else.

My system:
Intel Core 2 Quad
4 Gb Ram
GeForce 8500 Gt
Dual monitors :
Philips 244E DVI 1920x1080 primary
LG 20EN33 VGA 1600x900

KDE plasma 5.5.5
Qt 5.5.1
kernel 4.1.20-11-default
OS 64 bit

Refrash rate = 60,
Rendering backend = Xrender
Font anti- aliasing = on

I stuck with this.
Please guide me how to configure the video-system to avoid the eyes anguish.
Best regards.