HP550 laptop Intermittent backlight / inverter problem??

We have about 70 plus of these ordered in since last summer. We've only now had reports that the screen dims intermittently (no fixed duration of time) giving the effect that the backlight has turned off. The only way to get it back again is to make it go into standby and bring it out again. It is rumored to happen on various different laptops of the same model. We use the laptops on battery and that is when the problem occurs, so plugging them in can't really be a solution.

I've checked the bios and there are no related options to change there.

I've tried changing the graphics driver version, but my colleague has mentioned that it happened to him whilst testing and it stayed dim whilst he rebooted the laptop several times, so I'm guessing that rules out the driver.

I've turned off all power saving features.

The brightness settings don't seem to have any effect.

When it happened last the battery still had an 1 hour and a half left in it.

I haven't tried attaching an external monitor yet, but will next time to see what happens.

Has anyone else come across this yet? I'm not sure how often this is occurring to know how big a problem it might be, but if it is a faulty component, it could be a bit of a headache sending off all the laptops for repair.

I have the exact same issue. Recently purchased 3 and all exhibit this same fault. If you close the lid and open again the backlight kicks back into life.

Did you get anywhere with it?

We ran into something with hp 6735s laptops and discovered that the lid has a magnet which when place to close another laptop or it is put on top of another laptop the back light goes off. This has been confirmed by HP 2nd level as we thought it was a fault with the screen or driver initially.

Is it worth looking it from this angle?

Am guessing this is the problem with HP550?

HP 550 Notebook PC- HP Notebook PCs - Notebook PC Slowly Resumes From Hybrid Sleep - c01853817 - HP Business Support Center

We have about 15 of these, and seen this issue a few times, not had chance to test the above fix.

Exact same fault on one of 3 we bought. Change the setting to do nothing when the lid is closed. Then when you shut it and open it it doesn't go to sleep.

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Originally Posted by plexer

Exact same fault on one of 3 we bought. Change the setting to do nothing when the lid is closed. Then when you shut it and open it it doesn't go to sleep.

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Isn't that what will happen if you choose that setting? :confused: ;)

The issue is not with the unit going to sleep, but the backlight just truning off. The machine is still running as normal and if you look close you can still windows running.

I have had reports of it happening during use. Went the HP route against my better judgement, not again.

We've got a few of these doing exactly the same thing - I'm about to set one of my techies on to HP.

I'd be interested to hear how you're getting on though!

Ant

Hi Guys,

Sorry, I hadn't noticed that this thread had been updated.

Smadison, nice idea, but the latop screen darkened in front of me with no others laptops or other magnetic sources close to me.

Mullet_man, this support document doesn't quite fit. The issue is the sudden turning off of the backlight (even when actively using the laptop) and not any sort of sleep resuming.

I've contacted HP and they've been through the usual "have you tried this" scenarios and then agreed to take the affected laptop in for repair. I guess they would just replace the inverter / backlight, in the absence of not knowing themselves what else could be causing the problem. I haven't yet sent it off in case someone else comes up with something. Testing is a pain, as you have to wait for the condition to happen before you can rule certain steps out, and it doesn't seem to occur if you just leave the laptop to one side and not use it. Now my problem is that the laptops are reaching the end of their one year warranty. At this stage I'm guessing it is a hardware related problem more than a software / driver issue. Maybe a faulty batch of inverters in this model?? What OS are other people using that are affected? I'm using XP here. Any more updates from anyone? I'm tempted to maybe send one laptop off, get it back and see what they've done and then re-test to see what happens.

XP here we bought 3 of these and I've only had 1 reported with this fault.

Ben

XP also here.

64 of the buggers here... a fair few failed HDDs and about 3 or 4 with backlight issues. Running XP SP3.

i seem to remember having this problem a while back and iirc best solution i came up with was to shove vista on them and the problem went away. I THINK hp did release a bios flash but its been a while

Exactly the same problem here! (Amsterdam). We've only 1 laptop HP 550 for private use. The laptop has been 4 times (!) picked up for repair. The service of HP is very good, I notice. Just give a call to the HP global support number and often the next day UPS is at your door to pick up your laptop. You don't even have to pack the laptop yourself. Return is often in few days as well. In the case of the Netherlands, they sent it to Polen! This was the good news. The bad news:

4 Times sent away for repair is very anoying. UPS demands that you stay home between 08:00-17:00. The HP helpdesk is not very competent. They just go into the scenario: Did you do this and that? Of course a firmware update is 1 of those steps. It doesn't help. After first time pick up the display was renewed. Few days later the second repair the inverter was renewed. The third time repair the display was again renewed (?!) cause the helpdesk stated that I should have a guarantee of the 3 months on the first repair. After a few days the laptop came back and still the flickering problem there! With the 4th repair they changed the battery cause I noticed and told the helpdesk that the problem occurs while working on battery. But after the 4th repair, still the problem was there.

After that I was tired of it and wrote a complain letter to HP Customer Relation Management by email attachment. Already 2 days later they offered me a new model laptop with at least the same spec as the initial one. They offered me a choose of 2 and choosed for the HP Probook 6540b (WD683ET). This model is way better quality than the 550! Double price as well. So now I'm content with this solution and service in spite of the anoying period before.

What is quite stupid is that HP this display flickering problem doesn't identify as a world wide known problem. The helpdesk doesn't know anything about this issue and should read this topic. Or at least Googling on "HP 550 display problem".

BTW: What are your results so far?

An update although no solution on a larger scale,

I sent one laptop off just before the warranty expired. Got it back and the report said that the display had been replaced. Checked it for a while since the repair and it hasn't reproduced the same problem over a good length of time. This is all good and well, but I can't start sending off laptops just for screens to be replaced as we have 70 of them here. In fact I can't now because the warranty has expired. I'm sure also that HP would only deal with each one as it occurred and you wouldn't be able to say it happens to all our laptops of this model. I don't really like these laptops, they have crappy buttons that don't always work unless you press them in the middle, sometimes the laptop doesn't boot properly and you have to reseat the memory & or hard disk and the kids seem to like to rip the mesh bit off around the power button. All in all one big headache. I have resigned myself to just advise people to put the laptop into standby and take it out again.