Right the problem is the desktop is magnified about ten times so Ican't scroll about can anybody give me any clues on why this happened and waht tae do tae get oot of this problem

and your operating system is?
it it a laptop?
try this:
if windows
right click on desktop and select properties
hopefully you can see enough to click on the settings tab
you need to change the screen resolution down, start with 800 by 600.
click the apply button

hope this helps you

Had a similar problem after moving my ATI video card to my new PC, the desktop picture was absolutely huge when set at 600 X 800 screen resolution, at higher resolutions I could see the whole desktop but there was a 2" wide black border around the perimeter and the visible desktop was so small I could barely make out small details or text. Somehow in the move it set itself up for a dual monitor application, as soon as I reset it to single everything resumed it's normal size. Don't know what your setup is but that would be something to check.

try changing the htz seeting in the refresh rate of ya g card.u might be using a setting too high or too low and your monitor is struggling to handle it.start at 70 mhz if u can.