I don't believe it is. I get relatively low frames even with no output connected.Why did you never mentioned that in this thread before?When I connect an output (60hz) I'll barely get 30 frames.this seem to be your main issue....
To be fair I should be getting FPS much higher than 60 - Razer Blade, Windows 10 Home 64, i7-8750H, 16GB RAM, Samsung MZVLB 512GB SSD, NVIDIA GTX 1070 MaxQ - 430.64, 8GB VRAM.- your results showed that you can hit 60 fps and not max. 55 fps.
Unsure if this is relevant but tearing will sometimes appear in the output monitor but not on the output itself (with V-Sync is on).