My system is Dell XPS L502X, with NVIDIA graphics card 525M. For your notice, it is different from this and not completely related to this.
I was having problem of black screen after opening the Ubuntu 14.04. To get out of it I reinstalled Ubuntu 14.04.
After re-installing and adding NVIDIA drivers, system is getting freezed, frequently. So only option left is to press,Alt+F1, then Alt+F7
Are you sure it's 100% related to the video driver? You could try the following to speed up your computer, too:
Install the packages preload and prelink. These take certain actions to make the system faster.
Execute sudo apt-get install prelink preload in a terminal.
Reduce Swap usage. The default swappiness value is 60, which may be too high.
Open the file /etc/sysctl.conf and set the swappiness parameter:
sudo nano /etc/sysctl.conf in a terminal.
New line at the end: vm.swappiness = 10, then another linebreak, save with Ctrl+O.
If you apply these changes, your computer should get faster after a reboot.
For your touchpad, you should ask a new question, since this is another problem.
