Hello again...we have about +1000 of lcd displays in the fab, around 40% of it are flickering (but text still readable). Our facility staffs check all groundings from those flickering but all were fine. During investigation, the flickering goes out when using HDMI instead of VGA. But it is not cost effective to replace all with HDMI...Thus, we need some inputs from you experts on how this flickering happens when using VGA but other display ok with VGA. Need suggestion on how to resolve it in minimal cost. Thanks in advance.
What technical informations did you give that we can use to find a solution?
When a monitor flickers, then usually it's because
* monitor type: input signal range
* graphics card output signal: resolution, frame rate,
(Maybe even a mature "interlaced" signal is output by the graphics card)
* noise introduced into the monitor cable (signals): cable type, shielding type, cable length
OK today we found something new today....when we dont connect the ground to the cpu and monitor supply the flicker goes out. I mean from the ac power plug going to the pc/monitor only live and neutral connected (no earth ground), it works...So weird and not safe...any idea guys? Is there something need to do to the video card groundings or monitor groundings?
What do you expexct?
We don't know about the cable, the wiring....you just give vague and incomplete informations.
And it seems you don't read our posts....
What do you expexct?
We don't know about the cable, the wiring....you just give vague and incomplete informations.
And it seems you don't read our posts....
From one of the flickering unit ground & neutral is 1.36Vac....but from good unit is 0.7Vac....is it safe to add jumper to short ground and neutral from flickering unit? thanks
the flickering unit ground wiring has problem . Trace the ground wire and follow it to the point where it is actually grounded. There may be corrosion or even loose connections in the path.
the flickering unit ground wiring has problem . Trace the ground wire and follow it to the point where it is actually grounded. There may be corrosion or even loose connections in the path.
We have tried to connect the flickering unit ground and non-flickering unit ground using jumper wire but not helping....if the ground have problem, why using hdmi doesn't flicker...It flickers only when using vga...any idea guys? thanks
VGA = analog. Any influence in analog signals will be shown on the screen
HDMI = digital. More tolerant against noise, until the noise is big enough to make HIGH --> LOW ore vice versa.