I’ve finally sorted out my ATI graphics card driver in Ubuntu.
KSP is nearly as fluid as in Win7, but it’s in Linux so more fun 🙂

Helpful Pages

BinaryDriverHowto/AMD

RadeonDriver

What is the correct way to install proprietary ATI Catalyst Video Drivers (fglrx) directly from AMD?

How to install Radeon Open Source Driver?

Why Radeon Users May Want to Avoid Ubuntu 16.04 LTS

Is my AMD hybrid-graphics card supported by Ubuntu 16.04 driver?

RadeonFeature

What Linux drivers do I need for my Radeon HD 7850 on Ubuntu 14.04?

Ubuntu 16.04 Radeon HD7850 radeon driver CS:GO 0-4fps

And remember to test: /usr/lib/nux/unity_support_test -p