|If this is happening before windows starts loading then it must be a hardware problem. You could try connecting an external monitor to see if you get the same results.|
If this is happening only when windows loads then check in device manager and see if there is a problem showing with the display adapter. Also check display properties and see if you can change the number of colors and resolution to something better.
Your windows 7 disk may not have the necessary video drivers. If you're unsure if they're installed then go to the support page for your laptop and download the latest drivers.