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17" Viewsonic LCD monitor

I have a LCD monitor that powers up only when the VGA connector is not plugged in.

If I plug in the VGA connector the display lasts only for about 20 seconds the most and then it goes dead. Even the power light will not light up when this happens. The on/off button on the front also does not have any effect.

I've replace the main filter capasitor and a 0.33uF capasitor in the switching power supply but the problem is still there. The 5V from the switching power supply that powers the display board is present all the time(Even when the display is dead)

I've tried to leave the power on for about one hour and disconnect the VGA connector which gives me a "No Signal" message for about 5 seconds and then the power light remains on. At this state the monitor appears to be with any problem.

Thanks in advance.

Reply to
vernond
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For starters, how about a make and model and age information???

Reply to
hrhofmann

Stop farting around replacing parts at random. There are three possibilities:

  1. A bad regulator on the display board (there are probably three of them). These are usually three terminal SMT devices. Identify them by looking up the part numbers. Download the datasheets, and check the output voltage.
  2. Bad caps on the power supply allowing enough noise into the video card to cause the onboard regulators to drop out of regulation. Replace them all with good quality low ESR types like Panasonic FM or FC series.
  3. Bad caps on the display board. Again, replace with good quality parts.

PlainBill

Reply to
PlainBill47

You sure the resolution you're sending it is in range? Shutdown might be normal for wrong video rates.

G=B2

Reply to
stratus46

The model of the monitor is VA1716W. It's about 1 year old.

The main filter capacitor was out of tolerance, that's why I replaced it.

A few capacitors in the video board was also replaced, but the results were the same.

Will try to change the resolution and plugging it in again.

Reply to
vernond

On Sun, 7 Mar 2010 15:49:46 -0800 (PST), snipped-for-privacy@yahoo.com put finger to keyboard and composed:

VA1716w User Guide:

formatting link

"WARNING: Do not set the graphics card in your computer to exceed the maximum refresh rate of 75Hz; doing so may result in permanent damage to your LCD display."

- Franc Zabkar

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Please remove one 'i' from my address when replying by email.
Reply to
Franc Zabkar

Pretty rubbish design if it can actually be damaged.

Sylvia.

Reply to
Sylvia Else

Possibly this was carried over from a CRT manual by an ignorant writer.

It's not immediately obvious why this would damage an LCD display's drive circuitry.

Reply to
William Sommerwerck

My extensive experience tells me the LCD monitor won't function out of its specified resolution and sync. Mine will just say "out of range"

Reply to
Meat Plow

True. But the issue is damage.

Reply to
William Sommerwerck

I'll set my Samsung 760 LCD up on my PC, adjust the sync for 100hz and leave it cook for a few hours then get back with you.

Seriously, my interpretation is if the monitor input is out of range the drive falls back to a error state and displays the out of range message. In this state there will be no damage. Keep in mind that this applies to a specific monitor so your mileage may vary with others.

Reply to
Meat Plow

On Tue, 16 Mar 2010 18:30:01 +1100, Sylvia Else put finger to keyboard and composed:

I didn't believe it, either.

My AOC LCD just goes blank when the frequency is outside its limits.

- Franc Zabkar

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Please remove one 'i' from my address when replying by email.
Reply to
Franc Zabkar

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