Game engine stuttering

I have seen similar questions but none of the answers have helped with this. It doesnt show in the final export, but the whole time I am building the game, while I am testing, the game freezes about every second. Any ideas? I have tried every setting on my video card and my cpu is not overloaded.

When this is happening, I have had as little as a terrain, a 1st person controller, 1 light and no added scripts.