HP Pavilion dv5z-1000 black screen

I have a HP Pavilion dv5z-1000. On boot-up the laptop screen is black. I look at display with flashlight and no faint images visible. External monitor works fine. Toggle fn/f4.....nothing. I bought a used display panel on ebay. So, effectively replacing all of the components that everyone says could be causing the problem (lcd, video cable, inverter, backlight, lamps). My conclusion is that the replacement display is also bad. Can anyone think of any other reason for the failure of both displays. Thanks.

 

Yes, the GPU is shot. Common thing with the AMD GPUs in this model. They run too hot so the GPU separates from the solder on the BGA.

Remedy: new mobo or bake the mobo to reflow the solder.

 

How could the GPU be shot if it works with an external monitor?

 

Odd as it may seem, that happens with that Turion Ultra AMD series sometimes. Some of the solder bumps are good while a few others have cracked/separated from the BGA. In this case, the solder bumps corresponding to the circuits leading to the LVDS are bad or some such.

I had a TX2500 that had the same issue - LCD non-functional, external VGA functional. Baked the mobo and it was back to life.

There are some videos on the web which show you various ways to do a bake when you have to bake the mobo (when the GPU is soldered to it and not an MXM card).

 

Thanks for the info! I had read about the solder issues with this series, but was thinking none of the GPU interfaces would be working if the solder cracked or separated. But, after I think about it, what you say makes sense. I'm guessing that baking the mobo just postpones the problem and it will happen again at some point. Of course, postponing the problem is better than having to fork over the cash for a new one. How long has yours lasted?

 

GPU bake results can last from weeks to many months. There are a lot of success stories on this site.

I didn't keep mine long enough to experience issues after the bake. Maybe used it for 2 months. Went away for 9 months on a humanitarian mission. Came back and got an Elitebook2760p so I sold the TX2500 on eBay as a functional unit/or parts sale.

 

As a “last resort”, and to help confirm 2.0s likely diagnoses, you can also try putting the unit in a freezer for about 20 minutes or so. When I do this I usually remove the battery… but in reality I’m not sure it matters. When you pull it from the freezer take it straight to power right away and fire it up. I’ve done this a number of times and have even had a couple of units work for a day or two until they returned to your described behavior. Crazy I know… but it does sometimes work! Again... remember this is a last resort technique.

Best, Dave