Acer AL1715 black screen, weird scrambled signals, not ccfl problem.

[StevenT]

Hello

i have been searching on google to seek for an answer and a possible solution what is up with my monitor. I came across this link but i am not having a ccfl problem.

Its about an Acer AL1715.
The screen runs fine if im not playing a game, but when i do play a game (doesnt happen with every game and in some games the problem occurs more often/faster) the screen shows vertical lines (not game image, totally out of random vertical lines of every color you can think of, all mixed and scrambled vertical lines. Its not immediatly at starting up a game, sometimes after 20 mins into the game, sometimes after 2 hours.

To temporarily solve it, i unplug the volt cable at the back of the screen and replug it in. Immediatly the screen goes back to normal and auto adjusts the screen. Then after some random time (could be minutes/hours) the problem occurs again.

Gets annoying to always plug it out and back in, of course.

When the screen is showing all these colorful vertical lines, after a while (a full minute or 2) the screen goes black.

In the above thread i read some suggestions about looking for image or use a flashlight on it, mine does not show any image. (not ccfl problem right?)
The OSD is still accessible when the screen is black.

I can turn the screen on and of, but it does not solve the problem. Only pulling out the plug works (temporarily).

What is the problem with this screen and what are possible solutions?

i have already changed VGA and power cables, problem still occurs

thanks in advance

[aliasdck]

Re: Acer AL1715 black screen, weird scrambled signals, not ccfl problem.

I haven't come across a monitor with these symptoms but I have fixed a dozen acer al17xx monitors and 11 times out of 12 it was bad capacitors on the power board (but the symptoms were much different then yours).

Open up the monitor and take a look at everything inside. Check and reseat all connections.

Take good quality pictures of both the front and back of the power and logic board and upload them here.

[StevenT]

Re: Acer AL1715 black screen, weird scrambled signals, not ccfl problem.

i havent got it anymore since +- 3 days.
A temp fix i did was plugging the power cable in a seperate extender with power switch.
That works as a remote switch i can easily switch on and off with my toes under the table.
During any game when it happens, i can switch off and on and keep playing.

but recently i didnt even have to touch that switch with my toe, been playing games without the monitor problem.

[Krankshaft]

Re: Acer AL1715 black screen, weird scrambled signals, not ccfl problem.

Sounds like a main video board problem.

You have removed and reinstalled the LCD video cable into the main board right?

If so and it's not an intermittent cable connection then most likely it's a bad solder joint or thermally intermittent IC on the video board.

This is assuming the power being fed to the mainboard is clean and the caps aren't bad.

If those lines on the screen are present in the OSD it can either be the main video board or the LCD panel daughterboard.

When you load games some of them like to change the screen resolution as long as they're loaded if your desktop is at the display's native resolution that scaler doesn't need to work.

The game may be forcing the monitors on board scaler to work. It's reducing or increasing the pixel size to the LCDs native resolution. It could be this is generating added heat that's causing an intermittent joint or IC to act up.

It's a theory but based on your description the best I got .

The video board is about $20 bucks if you look around Acer part number 79020130. If that doesn't fix it the display isn't worth repairing.

[Krankshaft]

Re: Acer AL1715 black screen, weird scrambled signals, not ccfl problem.

In a worse case scenario it can be an issue on the driver board this little board is usually under a metal plate at the back of the panel. It contains the driver ICs (which can cause vertical colored lines) if you're lucky it could be in intermittent joint if you're unlucky it could be a intermittent IC or a problem with the panels bonded ribbon cable.

The first can be repaired the last two mean a junked panel.

The fact that you don't see the vertical lines on the OSD now that I think about it says nothing.

So a run down check all of the joints on the SMD parts on the main video board then check the driver board for bad joints.

[monpirri]

Re: Acer AL1715 black screen, weird scrambled signals, not ccfl problem.

Hi every 1 ,

This is my first post here ,its a hell of discovery this spot here ,I am very happy to find this tech community .

Well as a matter of luck I have my Acer 1716B with a weird noise ,good ccfl but real annoying black spots as if out of H sync signals.
Power supply is indeed well ,good caps +5 and +12 output really clean as in oscilloscope i dont see HF ripple.

Any clue is apreciatted

Monpirri