Dual Monitors: Unplayable FPS Drop

[vampyiscool]

So I'm having some issues running dual monitors on my rig. When I run just my main monitor, I get 300FPS in CSGO. Streaming gets me about 250FPS.

When I do dual monitors, I get sub 150FPS and when I stream, I hit around 75 FPS.

My Specs:
Core i7 6700k
GTX 1070

Main Monitor is a BenQ XL2730 running at 1440p at 144hz.
The secondary monitor is a BenQ XL2411 1080p @144hz

Thanks in advance

 

[Sedivy]

You'd expect a drop with that setup regardless, but I don't know if it would be that big of a drop. It might have to do with different resolutions. If you bring both down to 1080p just to test, is it as big of an fps drop?