Horribly Annoying screen tearing

Screen tearing happens when the monitor cant sync fast enough with the computer's graphical output speeds. Enabling Vsync will slow the fps rate of the computer to match the hertz setting of the monitor giving fluid motion.

Yeah I've tried that but it still does some screen tearing or just makes it lag a ridiculous amount

You could try using triple buffer but not sure if it will make a difference in the game you're playing as its apparently only meant for Opengl based games. If its a D3D you're playing then have a look at this thread.

http://www.guildwars2guru.com/topic/50705-triple-buffer...

Direct3d override will enforce triple buffering in D3D apps and might be the way for you to have less tearing and no lag. I haven't used it, so Vsync might still need to be enabled for triple buffering to work.

Higher the hertz in a monitor would also help, 120hz monitor would look awesomely better than a 60hz, a lot less tearing if the computer doesn't reach over that amount. But even with Vsync enabled on a 120hz monitor, the input lag would be near unnoticeable