144hz & 60hz display stuttering

Hey, I just got a 144hz monitor yesterday and now I'm using my old one as a second display. The 144hz monitor works great alone but if I plug in the 60hz monitor, both start stuttering and there is input lagg too. 144hz monitor is BenQ XL2430T and 60hz is Dell 2440L. I've tried plugging the 60hz on the on-board GPU but that doesn't help. My GPU is a GTX 970. Any questions comment below, thanks.

 

help.

 

halp.

 

Disable windows aero

 

It made it better however theres flickering now, when theres a refresh rate problem. Single monitor too with aero disabled.

I wonder if installing Windows 10 helps?

 

A noob with a nice monitor <<<< ADD MY MSN!

 

Do you have a good video card?

Some video cards aren't capable of displaying 2 monitors at once (bad ones).

 

GTX 970 Windforce

 

help.