MacBook screen going crazy colours

Resetting PRAM may help.

http://support.apple.com/kb/PH4405

If this does not help, contact Apple.

Best.

Your computer has a partition on the hard drive that contains Apple Hardware Test (AHT).
To start AHT please follow these instructions:

1. Press the power button to turn on your computer.
2. Press and hold the D key before the gray startup screen appears.
3. It takes a minute or so for AHT to start up and inspect your hardware configuration.
   While this is taking place, an icon appears on the screen.
4. When the process is complete, select US language and click the right arrow.
   You can also use the up and down arrows to select a language and then press the Return key.
5. The AHT console appears. You can choose which sort of test or tests to perform:
   • To perform all of the basic tests, click the Test button or press the "T" key or the Return key.
   • To perform a more thorough diagnostic test, select the "Perform extended testing" checkbox under the Test button before you click the Test button.
6. Note: Your test results will appear in the window in the bottom-right of the console.
7. To exit AHT, click Restart or Shut Down at the bottom of the window.

Some computers support the use of Apple Hardware Test AHT over the Internet.

If your early 2011 model came with Lion pre-installed use the Command+d keys to get the online AHT. If it came with Snow Leopard pre-installed the AHT ios opn one of the original system discs that came with it.

coolio666 wrote:

I tired turning on the comp and quickly pressing and holding the D key before the grey screen. I held it down for a while and then the Apple logo came up and the comp started as usual... it didnt start any kind of a process

When powering up for the Apple Hardware Test did you hold the OPTION and D keys?

Ciao.