No display on HP laptop...intermittent.

[Darvus]

Ok, for once I have a question rather than a possible answer...

My client's laptop is an old HP Pavilion ze4600. When he brought it in, the LCD light was on, but the screen was black. I assumed it had crapped out trying to resume from hibernation. I hard-powered down and brought it back up. Voila...came right up no problem. I added memory (he only had 256MB installed and with shared video...yeah...not speedy), cleaned up the drive, reinstalled Norton 360 (don't get me started...told him we'd be changing that as soon as the license expired), and got it running better than the day he bought it.

Here's the problem...that was last week. Today, he calls me with the same (seeming) problem. When he got here, I tried the same solution to get it running. No luck. The backlight comes on as per usual, but I don't even get the HP bios screen! This tells me it's NOT a driver problem. I let it run as per a normal boot cycle and the HDD eventually calmed down and the screen even did a blink-out for a second as it does during normal booting. Once the drive stopped accessing, I did a Win-key shortcut to shut down, waited a few seconds while the HDD went nuts, and it shut down like normal. This tells me that Windows is running just fine!

To make matters more interesting, I tried hooking up an external monitor. The monitor is known working. Crap picture, but it works. Unfortunately, it wasn't getting anything from the laptop. Tried a cold boot and everything. No picture. At this point, I'm getting a bit worried...there's apparently no video signal AT ALL.

During the most recent bootup, I started hitting "Fn + F5" (the display selection hotkey) repeatedly. Now, I realize that this is a lot like hitting "ESC" during a command-prompt function instead of Ctrl-C and really doesn't DO anything...and yet, suddenly, there's the Windows loading screen on the laptop!!! Still nothing on the external monitor, but the laptop screen is working again.

I checked the Windows logs and found no errors of any kind. Seems I did my work well last week. Unfortunately, despite cycling through the display settings (Fn + F5) from within Windows, I still couldn't get anything on the external. This includes "external only" mode where the laptop LCD is turned off. Nothing.

So, here's the actual question: is it possible, or perhaps likely, that the video processor itself is malfunctioning? I mean, no external display, and intermittent loss of the LCD picture seems to indicate this, but I have little way of determining for sure. Any suggestions on another cause or possible solution other than having the laptop replaced?

[Darvus]

Oh, man...you're kidding...nothing? No suggestions, hints, thoughts, or anything?

Crap.

Well, as of right now, the screen hasn't gone out again, so I'm going to assume this is "resolved" for now. There's still no output to an external monitor (although the laptop DOES recognize that one is connected, as does the monitor...weird.) I'll leave this up for a few more days as "unsolved" to see if I get any responses. I promised my client I'd keep an eye here just to make sure, but I gave him the laptop back. At least, in case it happens again, I can remote-access now to try something that way.

I hate unsolved mysteries...(though, ironically, I loved the show).

(*Moderator: if you think this would get a better response in another forum, feel free to move it to the appropriate location. Thanks.)

[dogbreath077]

Here goes, find the specs on your motherboard and find out if your video card is integral or separate. If it is integral then I would say another mobo, but if it is separate then remove, clean and reinsert and retest, then repost with results. This sounds like a loose connection, or a crack in the motherboard. repost please, cya then.

[Darvus]

Although I agree it sounds like a loose connection, I couldn't find anything loose at all. Nothing burnt, nothing cracked (that I could see), and nothing out of the ordinary. As for integrated vs separate, I've never heard of a laptop shipping with anything but integrated video. It shares the system memory and is not something you generally hear of being replaced.

If the on-board chip is bad, then yeah, the motherboard would need to be replaced and that's just not worthwhile. I just didn't know if there was another test I could run or any other way to be sure, since I'd never run across this particular issue before.

I've spoken with the client recently, and he's had no further trouble with the screen crapping out, so we're figuring this is resolved for now. That is, until he finally replaces it (which he's been considering.)

Thanks for your help, but I think this thread is due to be set as "solved".

[melrio9785]

ok...so, i think there should be a recall on some of these, because I am having the same issue...2 months AFTER my warranty expired OFCOURSE! anyway, I have an HP dv2120us notebook & when I boot it up now there's no display whatsoever...not even on an external monitor. i guess i'm going to break into it today after class.

what are your thoughts?

thanks,

Melissa

Although I agree it sounds like a loose connection, I couldn't find anything loose at all. Nothing burnt, nothing cracked (that I could see), and nothing out of the ordinary. As for integrated vs separate, I've never heard of a laptop shipping with anything but integrated video. It shares the system memory and is not something you generally hear of being replaced.

If the on-board chip is bad, then yeah, the motherboard would need to be replaced and that's just not worthwhile. I just didn't know if there was another test I could run or any other way to be sure, since I'd never run across this particular issue before.

I've spoken with the client recently, and he's had no further trouble with the screen crapping out, so we're figuring this is resolved for now. That is, until he finally replaces it (which he's been considering.)

Thanks for your help, but I think this thread is due to be set as "solved".

[darsh999]

first of all their is no problem regarding your motherboard so keep this out of your mind
and yes i think the HP service center will not replace the laptop but they'll definitely replace your laptop's screen if it is in warranty lol.........

[david1185]

darvus your GPU got fried/burned because the cooling fan was not circulating air thourgh the laptop, the gpu share the same heatsink, but the gpu(video) will burn quicker than your cpu. if you think is b***** open up you laptop and take out the heatsink fan and send me an an email [e-mail]

[Darvus]

As old as this thread is, some people are still posting to it. This is just a followup to end this thread on a completed note.

A few weeks after the initial problem I posted about, the problem happened again. In the end, I ended up declaring it dead.

When running the system (no video, again), I noticed it was getting VERY warm near the top of the keyboard, off to the left. I shut it down and dismantled it to find the cause, keeping in mind where I was looking. It looked like a couple components on the board, covered by the heatsink, were causing this. When I tried to remove the heatsink, I noticed a crack in the solder holding one of the components to the board. I'm not generally rough with these things and while old thermal compound can work almost like epoxy, I've never managed to break a solder joint removing a heatsink before. The other, identical, component next to it was undamaged and didn't budge under pressure.

My diagnosis is that this was a video component that had failed, or was failing, and the heat it was producing weakened the solder. I'm not as knowledgeable about core electronics as the components they comprise, so I don't know what that component was specifically, but it was obviously a core piece of the display system.

The heatsink and fan worked fine, as I'd cleaned them out already, so I think the heat was the result, not the cause, of the failure and that the cracked solder was just another pointer to the already failed component.

In any event, I recommended my client get a new system.

Thank you! I appreciate all the suggestions.

This thread is (unofficially) closed. Please do not reply to this again.

[avijit4all]

i opened a laptop for cleaning ..i cleaned it by opening and fixed it again now its not showing the display everything else is working.its booting up but no display..