I have in my possession one of my friend's laptop, an HP Pavilion DV-4. She recently needed to replace the battery since Windows reported that her old battery needed to be replace since it couldn't hold a charge. She got the battery, replaced it, and that's where the problems began...
The laptop starts up fine, boots into Windows normal, but the screen itself doesn't work, a full on black screen. I have it connected to a VGA monitor to test if the graphics chipset is fine. It worked fine for the first five minutes on VGA with perfect color and all. Then it went weird and now there's a blue tinge. I tried to hook it to an HDMI monitor and started up the laptop, but the BIOS hung saying that it's "Preparing to boot to OS" and does nothing.
On HDMI, the BIOS doesn't have a blue tinge, on VGA, it does.
I looked at the replacement battery and it was 11.1 volts, it should be 10.8 like the original. My conclusion that I drew from this is that the battery slightly overvolted something, either the LCD screen, the inverter, or maybe a voltage converter. I'm now thinking the graphics chip is also damaged...
OH, I already tried power cycling it, so any comments and suggestions on what you guys think would help. I'm trying to get a second opinion.
I have yet to crack the sucker up and see if there's a loose connector.