Laptop monitor cutting out

[Akill]

Hey once again guys!

ive been given this HP pavillion laptop to have a look at, the situation is pretty weird :/

basically after much testing and such the problem can be described as this: the laptop seems to work fine EXCEPT the monitor doesnt turn on, there is no backlight to it either proving that it must be powered off. In odd scenarios the monitor will turn on with the rest of the system but power down shortly after boot, sometimes reaching the desktop before doing so. note that even if the monitor turns off, the rest of the system appears to function normally. My friend normally runs his laptop from the mains without the battery connected, and there seems to be a correlation with the monitor turning on to start with and the battery being connected, if the battery is out the monitor seems not to turn on at all.

I was forced to conclude its some sort of power problem after at a first glance thinking it was a graphics hardware issue. I have tried connecting the laptop to a desktop monitor without avail, however i cannot be sure if its because im not getting that to work properly or because its part of the problem (i have to work blind once reaching the desktop)

the problem arose at first as a 'serious graphical error' according to windows after it would turn itself off shortly after having the graphics card come udner full load (from booting a game) apparently it got worse from there to the point described above. The start of this problem lead me to the first conclusion of a graphical issue. and when it started acting strange before booting windows i narrowed it to a graphical hardware issue, or power problem.

Does anyone have a clue whats going on?

[master811]

does it happen on every boot now then (with or without the battery), I take it not something related to overheating of the GPU? Does windows give any details in the event log at all? or any bluescreens?

[Akill]

if there is a bsod i wouldnt be able to see it lol. the monitor cuts out far before i could attempt to read the event log.

a week or so ago my friend actually took his laptop to a computer repair shop, who charged him £50 to clean the laptop of dust who claimed that the graphics card probably was overheating. But unfortunately the problems persisted as soon as the laptop got back from the shop

[ineedanerd]

Does the external PC monitor or TV out port work?

[peterb]

You didn't mention which specific model of HP Pavillion you have, but fwiw, my daughter had a similar probvlem with hers. Fortunately it was just within warranty and she RMAd it. The report sheet said that the screen had been replaced, so my guess is that it was a backlight (or inverter) problem. However she did say that a monitor connected wouldn't work either, but that could have been a configuratioin issue - I didn't look.

Can you see a 'ghost' image on the screen under a bright light? (Sometimes you can if the backlight fails) That would confirm diagnosis.