This is simply an issue with your model render distance which is a setting in the 3D view settings.
The 3D view settings can simply be found in:
Tools -> Options -> 3D views
After that simply drag the slider until you have a distance you approve of, as it will change the distance of which models turn themselves into yellow boxes so your PC doesn't load it.
Bare in mind having it up fairly high while working on large scale projects might cause some lag. So it's best to not turn it up too high.