When booted screen turns upside down help please !!

[Guest]

Hi

I have a used computers for years and have just brought a laptop used.

It runs fine but when windows xp desktop comes on within a few seconds the
screen goes black and then either turns sideways or upside down with the
mouse following ( mouse up and on screen it goes down etc)

Please can anyone let me know why this happens and how to get it to normal.
It is windows xp home edition. I do have xp pro , is there a way install xp
pro without formatting disk and losing everything ?? Should i just format and
install windows again ? as it also wont allow me to go into personal settings
to changes passwords.

Please help

 

[JP]

probably you have set a flip option in ati / nvidia control panel.