Laptop display gone wild. Help!

June 10, 2011 2:03 PM

Is my (partner's) laptop display kaput? It alternates between a blank screen (although the backlight is on) and strange wavy pink-green effects. The system outputs to an external monitor, and I've updated the bios and display drivers. I have also taken off and apart the screen to check the cable connections, with no change. What's happened? Motherboard? Display? Cable? Specs inside.

The system:
2007 Dell Latitude D820
NVidia Quadro NVS 110M graphics chip
Windows Vista 32 bit

I've read about the problems with this chip which led to the Dell warranty extension and the NVidia settlement. It appears that it's too late to claim benefits from either, so I'm on my own here (right?)

The effect is also strange. From my research, when screens fail it's usually in a jagged-horizontal-liney type of way. This is more like a flowy-lava-lamp failure. This is the best image I could capture. (That's the laptop running on the external off to the left.) I can usually make the effect happen when I hit the Fn-F8 combo that swaps between external and onboard displays. Anyone seen this particular failure before?

Finally, it looks like replacing either the display or the mobo will cost $100+, but the connecting cable can be had for much cheaper. Is there a chance that would fix it? Is there anything else I could try, or should I start shopping for a new laptop?

posted by Wulfhere to Technology (3 answers total)

I've seen this before. First off, it's most likely not the chipset. When these chipsets failed they would eliminate all video, both the screen and the external output. That being said, it could be a crack, liquid damage, video cable, inverter or a randomly dead LCD. If the LCD is cracked you should see black blobs appear near the edge. These take up to one week to fully develop. Because there's no obvious crack, a crack would be on the edge and hard to spot without disassembling the top half of the computer. If it is cracked, take precautions to not touch liquid crystal, as it is toxic. Blue nitrile gloves should suffice. A damaged video cable can cause this issue. You would need to pull it apart and look for any damage on the video cable. The LCD inverter is a small board that can cause this when it becomes defective. Liquid damage, as in an external liquid such as water, coffee, coke, etc. that got into the LCD itself can definitely cause this. The telltale sign of liquid damage is that you'll find residues of liquid on the metal edges of the screen. Lastly, the LCD can just die with no real reason. I know, it's a suck answer, but it does happen.

Liquid damage and cracks are only cured by replacing the LCD screen. They are showing up for around $150 on froogle. Video cable shows for around $13 on froogle. Inverter shows up for $26 on Amazon.

Disclaimer, etc: IANYLaptop Repair Guy. In the past I did work in regard to large volumes of laptop repair, including different models that had the Nvidia chipset failure. The above advice is based on seeing hundreds of laptops come in with various video issues.
posted by Mister Fabulous at 3:31 PM on June 10, 2011

It won't be the inverter, that just makes the backlight turn on.

It might be the cable, but I kind of doubt it. That failure looks a lot more like the panel has just gone nuts. (Technical term.)

My parts guide shows the part numbers for the panel to be:
YJ620 15.4 WXGA LCD Service Kit, D820/M65
YJ623 15.4 WUXGA LCD Service Kit, D820/M65
YJ624 15.4 WSXGA+ LCD Service Kit, D820/M65

And the cable to be:
GF120 LCD Coax Cable, D820/M65
posted by gjc at 4:21 PM on June 10, 2011

Response by poster: Thanks for the input so far. I may pull the cable out tomorrow and test it pin-by-pin with a meter. I'm pretty sure it's not cracks or liquid, as it's a well-cared for machine, but I'll keep an eye out for that type of damage too.
posted by Wulfhere at 5:14 PM on June 10, 2011