slow graphics when laptop display is disabled

Hi,

I have put a laptop into a docking station and want to use it with an external

monitor (and keyboard and a trackball) when I have it at home.

The external monitor is connected to the docking station. When I disable the

monitor of the laptop in the KDE system settings, or when the lid is closed,

graphics are unusably slow. When the monitor of the laptop is enabled,

grahpics are at normal speed.

This is an HP zbook G2 in it's 230W docking station, connected to a monitor at

1920x1200 pixels, running Fedora. NVIDIA drivers aren't installed --- do I need them?

What can do I to use the laptop with the lid closed and it's monitor disabled without it getting so slow? Is this even a KDE issue?

lspci | grep VGA

00:02.0 VGA compatible controller: Intel Corporation 4th Gen Core Processor Integrated Graphics Controller (rev 06)

01:00.0 VGA compatible controller: NVIDIA Corporation GK104GLM [Quadro K3100M] (rev a1)