Confirm diagnosis - flickering LCD screen in HP dv5 laptop (see video)

therealmatt

Honorable
Feb 27, 2012
2
0
10,510
I know this subject has come up a million times, but I just want someone to confirm my diagnosis before I tell my friend to buy a new LCD screen for his laptop. It doesn't make sense that it's a bad LCD, otherwise I wouldn't ask.

I also haven't seen any other videos of flickering screens that look exactly like this, so please take a quick look at the following video:

http://daybreakdrive.com/ABND/Lemax/lcd.html

This started after I re-applied some thermal paste to fix an overheating issue. (Per the application instructions on Arctic Silver's website, I used 91% isopropyl alcohol and a lens cleaning cloth to clean the CPU die and heatsink surfaces, then I applied the new paste as directed.) Feeling like it went well, I put the laptop back together to test for overheating, and my heart dropped when the screen would only flicker for me. I then hooked the laptop up to an external monitor and thankfully it displayed just fine.

I've taken laptops apart before, and having encountered a flickering screen in the past, I ordered a new LCD cable which I installed VERY carefully. This unfortunately did not fix the flickering. The screen was working fine before I took this thing apart the first time, and since I didn't even touch the display assembly the first time, I don't understand how the screen itself could have been damaged.

So, do you think I just have 2 bad LCD cables or is it really time for a new screen? Is there anything else that would cause this flickering?

Thanks in advance.
 

golfer91

Honorable
Jun 13, 2012
1
0
10,510
I have this exact same problem. Have opened my computer up three times to clean the fan but have only had this problem since the last opening.

Ordered a new cable, installed and same problem. Works fine with external monitor.
Im not sure if it is because i did not apply thermal paste to the other parts of the heat sink, I am going to open up the computer again and give it a go.

Otherwise I have been searching the internet for answers for several weeks and have not found an answer. If anyone has a suggestion could you please let me know.
 
It is the screen but, to me it looks to be an LCD Inverter (within the screen bezel) issue - quote from eHow:
"When to replace
When an LCD inverter is going bad and needs to be replaced, the light to the monitor can either go out altogether, go out after a brief period of usage, or flicker on and off; the much dimmer image can sometimes still be seen on the screen."
There are quite a few articles I found on testing/replacing lcd power inverters and they can be found (usually) cheaper than entire screens.
Could even be as simple as a loose connection on the power inverter - worth looking into I think.