Screen flickering on vista boot sequence

i had problem with a piece of software i put on my new vista laptop, could
not get rid of blue screen of death, so i used the recovery disc that came
with the laptop to remedy the problem.

everything seems ok except that during the vista boot sequence just after
the scrolling bar the screen seems to turn off for a few seconds then
flicker quickly and switch back on just before the logon screen.

this did not happen before when the laptop was first delivered. i am
wondering if this is a fault or some sort of driver loading part of vista.
apart from this the laptop seems perfectly fine

any help would be grateful, have tried to ask in other forums but not much
help.

mark