Terrain Detail causing Gfx.WaitForPresent to take 3/4MS??

I have a terrain, and i painted some grass on it. I turned the opacity down a ton, it’s not THAT much grass.
My problem is, it reduces my frame rate SO much. The CPU frame processing time is 2.0 MS without grass. With JUST this grass turned on, it’s 4.5 MS, dropping my frame rate from 500 to 220. Why is my grass so incredibly graphics intensive?

I have detail resolution per patch set to 32. All help is appreciated on how to speed this up…

I discovered something funky!!

So I open the profiler, and when i have grass disabled, the camera renders in 1.08MS when I turn on grass it renders in 1.12MS, BUT Gfx.WaitForPresent goes from 0.29MS to 2.10MS.

So GFX.WaitForPresent is appearing when i turn on grass, and it lags my game a lot, and the grass is only doing a +0.04MS increase (Which is way better than 2MS Increase like i previously thought when i believed it was coming from grass)

When I reduce the terrain’s detail density, the GFX.WaitForPresent time drops too… Not sure what’s going on.

Bump