HP DV6 - Powers On but Blank Screen - Caps Lock & Num Lock *NOT* flashing. *Video Available*

[anwix]

I'm ruling out the possibility of a GPU failure, cause I've had a fair few HP DV6's that have had a bad GPU, but this is nothing like that.

The Caps Lock and Num Lock do not flash continually.

However, upon powering on the laptop - within the first second, they sometimes flash for a very, very brief moment.

I've tried the usual:

- Removing the CMOS battery for a few minutes and reseating it.
- Removing the battery + power adapter and holding down the power button for 30 seconds, before powering everything back on again.
- Changing RAM sticks with other perfectly good ones.
- Changing the HDD.
- Plugging it to an external display

I've even removed both ram sticks - because this laptop has an onboard speaker capable of producing beeps - however, no beeps were heard even after removing both ram sticks and powering laptop on.

Disassembled the laptop, nothing was burnt on the board or damaged.

The laptop was working flawlessly up until a few weeks ago. Turned it on one morning and there was no display. It didn't stop working gradually. There weren't any BSOD or freezes or a gradual decline in performance. It just happened suddenly.

Hasn't suffered any accidental damage and on the whole, the laptop has been well kept.

Video of what it's currently doing: https://vimeo.com/124508610

^^ The ticking that you hear in the video prior to the laptop being started is from my own custom build, it's coming from the PSU and has been that way for over a year, I've checked the PSU and there's nothing obstructing the vents inside. Don't know what's causing the noise, but any input would be nice! Cheers.

I need a sure way of knowing that it's definitely the motherboard and not the CPU, I need to know whether I can do anything myself to fix it or whether I need to buy a new Motherboard/Laptop.


Thanks.

 

[anwix]

Bump. Anyone?

 

[ffg7]

disconnect the laptop screen from the motherboard as ran into similar problem early last year which ended up an inverter board for the screen developed a short in it. removed the inverter board & the laptop posted on an external monitor.

 

[anwix]

This is going to sound odd. I was just on my way to do that, I partially disconnected the laptop, battery and charger were out, only had a hdmi plugged in. Funny thing is, the backlight on the back of the laptop - on the HP logo - stayed on... Removed the HDMI and obviously the light was gone. But I'm not sure whether this is usual or not? I could have sworn that the light shouldn't be on if there isn't a battery or AC jack plugged into the laptop?

 

[anwix]

I tried a reflow, and after putting everything back together, the caps lock and num lock are blinking twice roughly every 3 seconds. According to the HP site this means that the bios is corrupted but having followed their steps to recover the bios, I've had no luck.

Any suggestions?