HP nc6220 - Black screen

[McK1987]

Hi fellow techies!

I have a HP nc6220 which when I switch on, I get the green light on the power switch and I can hear the fans. However, the screen remains completely black. No BIOS screen or windows loading creen and it doesn't even look like it is slightly dim, it os completely black. Now when I plug in the charger, it detects and charges and also the laptop never turns itself off when on the AC power.

I have tried putting in an external monitor but I was unable to have anything on that screen as well.

Any ideas guys?

Cheers in advance!!

 

[wimwauters]

eBAY is full of these. Most likely a faulty motherboard.

Try running it with the battery removed.

Get spare parts on eBAY, working on these isn't too bad.

 

[McK1987]

Thanks for your response.

I did think about purchasing one from ebay just for the parts but as I wasn't sure of what the real cause was yet, I haven't bought any spare parts yet.

I think I will now though as it does seem to be too good a laptop to just give up on. Just wish I could test it out with a part before I buy so that Ican use process of elimination to determine root cause.

Thanks Again!

Any other suggestions welcome and would be appreciated!

 

[meanderer]

1. shine some flashlight on the screen see if you can get a feint image
1a. connect it to a external monitor, see if you can get an image.
1 -> if you do, then it's a screen issue, relatively easy to fix
2. the graphic chip has bad solder connections, a very very common problem on the main board at this age, especially with hp with nvidia chipsets. I tried a hot air reflow on 3 of these guys and they all revived to a certain extent.
3. Power MOSFET is bad, but usually these won't even cause the LED to light up.

 

[MobileTechie]

Probably the graphics chip.

Now's your chance to get your hot air gun and fancy IR thermometer out and have a crack at it. Go on - you know you want to!

 

[meanderer]

I tried to probe temperature of reflowed chip with those IR devices. doesn't seem very reliable so I have been doing it blind.

If you have any pointers I would love to know. I am using an Aoyue 852A. shield my chip with a few layers of foil and blow it 1 inch away for 4 minutes at 420 (I don't even know if it's F or C XD ) Problem seems to come back after a few weeks... so every few weeks I have to do it to 2 machines because those are my own lol.

 

[MobileTechie]

I don't think hot air stations are really powerful enough. I used the same model and used an IR thermometer and it took a lot longer than 4 mins to get up to temperature. More like 15 or 20.

I know what you mean about the thermometer accuracy.

 

[McK1987]

Does anybody have any tutorials, videos, guides or instructions on how to carry out such a task?

I have to admit, I have never actually to on the faulty graphics on a laptop board. I have seen the issue many a time but never actually decided to take it on.

Cheers

 

[meanderer]

there's a thread in another section of the forum discussing this.
http://www.technibble.com/forums/showthread.php?t=18497