Stevo 4257

Hi, Can anyone help. I have a samsung R700 laptop, I recently upgraded my operating system to windows 7 which I purchased from Microsoft. My problem is that my screen keeps going blank on me. I have changed all my hiberenate and sleep settings to never but it still goes blank. This happens intermitantly more on initial start up but also happens after I have been on a while I don't lose anything when i reset but it is just a pain having to do it all the time:confused: p.s. may not reply straight away off to work.