LG flatron L1718S - shaky picture when not in native resolution

[bocca]

Re: LG flatron L1718S - shaky picture when not in native resolution

U101 - part number:
A1
AS1117L-33
B0612

pin 1 = 0.00 V,
pin 2 = 3.28 V,
pin 3 = 5.19 V


U102 - part number:
A1
AS1117L-18
B0544

pin 1 = 0.00 V,
pin 2 = 1.63 V,
pin 3 = 5.17 V

[retiredcaps]

Re: LG flatron L1718S - shaky picture when not in native resolution

@retiredcaps:

i attached the logic board photo

U101 and U102 are your voltage regulators.

1) Put your multimeter on 20 V DC if manual range.

2) Put your black probe on a ground screw (any one on the logic board will do fine).

3) Put your red probe on each voltage regulator pin EXCEPT the big fat tab. If the middle pin is "cut" and not touching the board, we want to measure that pin as well.

4) Report the part number for each regulator.

5) Report all your findings like the following example,

U101 - part number AL1117-33
pin 1 = 0.00 V,
pin 2 = 3.3 V,
pin 3 = 5.0 V

[bocca]

Re: LG flatron L1718S - shaky picture when not in native resolution

Just to note one more thing. When I enter the display menu, the menu part is not shaky but normal

[bocca]

Re: LG flatron L1718S - shaky picture when not in native resolution

@retiredcaps:

i attached the logic board photo

i measured the two voltages, and they are both 5.21v. seems normal to me

@Th3_uN1Qu3

i tried few cables, including test cable that's 100% working. As i previously said, tred switching video cards but to no avail. I also tried another computer completely.


One thing i noticed is, when i switch refresh rate from 75 to 60 hz shaking is reduced by about half but still clearly visible across whole screen

[Th3_uN1Qu3]

Re: LG flatron L1718S - shaky picture when not in native resolution

That is usually the fault of a bad cable, or weak signal coming from the video card. Before messing around inside the monitor, have you tried another cable and another computer?

[retiredcaps]

Re: LG flatron L1718S - shaky picture when not in native resolution

1) Post a picture of your logic board. There may be some voltage regulators that are failing?

2) Are your voltages on the power board stable? I see the connector says 5V DC. Is that stable going to the logic board?

[bocca]

Re: LG flatron L1718S - shaky picture when not in native resolution

1. 1024x768, 800x600, it's all the same. As I said any 1280px by long side works fine
2. Yup. Tried 60hz, 75hz, no difference
3. Tried several of them, no change. Some are middle class, some are strong gaming ones
4. win xp
5. yes, drivers are correct. Problem is not software based, i'm pretty sure
6. tried it, no difference
7. Old problem. Monitor stood on a shelf for half a year, and now I tried to repair it.

thanks for replying

[selldoor]

Re: LG flatron L1718S - shaky picture when not in native resolution

Hi - so what resolution did you want to use?
Did you try changing the refresh rate?
What Video card are you using?
What OS are you using?

Have you got the correct drivers for the Video Card and for the monitor/system.

Can you try the monitor on a different sytem.

Did it just start doing this or is it a new to you monitor

[bocca]

Hi!

So I have one of these, and it's got a shaky picture when not in native resolution, which is 1280x1024 btw. In a matter of fact, any 1280xXXX resolution stops the shaking and makes picture normal.

I looked over the PCB, ali it looks ok. No bulging caps, no busted fuses.

If you need a video of the thing, i'll make it.

Here's a pic of the PCB attached