Pat
     This is a fairly modern laptop in that they are still selling them.

Your graphics card will most likely be a AMD Radeon HD 7640G
The drivers may well be corrupt and you need to reinstall them.
1. You should run "System restore" and this may well put back any part of the software you may have "fiddled " with as it backs up you files before it allows you to do anything to the present set up.

2.On your computer screen bottom left click there and then click on computer. Look on the top left after you have clicked on computer and you will see a heading called "System Properties" click on that heading and it will give you the full spec of your laptop and tell you which graphics card after you have clicked on the left hand menu "Device manager"

You can download and reinstall the drivers if you do not have system restore active from the site below.

http://www.official-drivers.com/articles/amd-radeon-hd-7640g-driver

3. Get in the car and take it to the shop.

4. Do what I am doing right now typing whist having a nice Bombay gin with a Schweppes tonic and lots of bergs and veg (Ice and Lemon) hmmmm Lovely.  8-)

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