HP tx2500 tablet blank screen problem

Hi Guys,

could you know anyone that can help with my blank screen problem?
I have an hp tx 2500 tablet running on windows 7. i guess the problem started the first time i connected it to tv via VGA.
Days later, the screen would go blank on start up and would have to use the F8 and F10 keys to restore it.
I thought the BIOS was outdated so I updated from F.05 to F.OF.
When I change the resolution from High performance to Balanced Performance - or vv - the screen goes blank most of the time. Switching from one user to the next also brings up the same issue.
Sometimes I have to do 10 restarts to see what I am doing. I dont think its an ATI radeon problem cause i just got an update from manufacturer.
I suspect there is a conflict that was created the first time I connected it to an external display as it hasnt been behaving as it should since then.

Many thanks in adv.

The motherboards ATI video chip may be failing, or in need of a reflow

Thanks mate.