I removed all packages associated with NVIDIA from Synaptic Package Manager and installed nvidia-current. When I click NVIDIA-Settings, gives an error like this: You do not appear to be using the NVIDIA X driver. Please edit your X configuration file (just run `nvidia-xconfig` as root), and restart the X server. Please help me, I need your helps. My laptop model is Dell Inspiron N5110 using Nvidia GeForce GT525M..