[cctalk] Problem with Dell Vostro 1700

I have a Dell Vostro. When I boot, the screen briefly flashes and then remains dark. I have another one on which the screen would stay lit for a minute or two, then go black. If I closed the lid and opened it, it would stay lit for a few more minutes, then go black again. I corrected that by replacing the backlight power supply. In this one, is the problem more likely a defective power supply for the backlight, or a defective backlight, or something else? Thanks, Van Snyder