Pavilion DV4t-5100 will not boot after automatic HP Update.

After letting Hp Update do an update on my laptop and my girlfriends laptop, both computers rebooted only to a point where the power light and F12 light are on. The screen is black...nothing. Nothing displays on the screen at al at any point in time after power is turned on. Both computers are the same model. Bought at the same time 2 years ago. Called HP Support and they took me through a variety of things including removing hard drive and RAM and reseating. No luck. For $190, hP now wants me to send it in as they think it is a hardware issue. We find it very hard to believe that their update would cause hardware problems to one, let alone both machines.

Our question, has anyone had similar problems after an HP update has run? If so, any advice?

Thanks in advance....