I’ve spent alot of today playing with Ubuntu and Unity, I noticed that when Zooming in, the graphics tore and windows where slow to drag. I found this on the Ubuntu forums which seems to do the trick and make it super smooth.

ATI Radeon GPU’s

1. Install fglrx driver (stock driver is choppy…); to do this, just open “Additional Drivers” application and select “ATI/AMD proprietary FGLRX driver” (do not use post-updates/release), then click “activate” and wait for it to finish. EDIT: if it doesn’t appear in the list, your hardware may not be supported.
2. Open “AMD Catalyst” (after reboot !)
3. Enable “tear free” desktop option (one will find it easily)
4. Open compiz config (command: ccsm)
5. OpenGL plugin, untick the Sync to VBlank, Texture = BEST, Lighting effect ON (be careful here, to open the settings, click on the buttons and NOT on the tick/untick for the element, or entire desktop will disappear).
6. Composite plugin, Detect refresh rate unticked, set the refresh rate at double your video frequency (in my case 60 Hz, I set it to 120)
7. Close compiz
8. Log off
9. Log in again, it should be now smooth as silk and tear free

NVidia GPU’s

A variant of this seems to work as below just change the Compiz settings

1. Open compiz config (command: ccsm)
2. OpenGL plugin, untick the Sync to VBlank, Texture = BEST, Lighting effect ON (be careful here, to open the settings, click on the buttons and NOT on the tick/untick for the element, or entire desktop will disappear).
3. Composite plugin, Detect refresh rate unticked, set the refresh rate at double your video frequency (in my case 60 Hz, I set it to 120)
4. Close compiz

Link to: Original information on Ubuntu Forums