Connecting LG Plasma via HDMI with PC - flicker problems

[TjS2011]

Hi,

I just bought a 50" LG Plasma screen (LG 50PV450) and planed on connecting it with my computer. Its a Win7 with a Radeon HD 4800 graphic card that has a HDMI, VGA and DVI output.
I connected the screen via HDMI with the computer, set it to 1080p and adjusted the refrate to 24hz. The picture looks awesome, though I have a very subtle but visible flicker in white areas (white not moving areas, e.g. on a website). The flicker is also more visible from the corner of my eyes if I dont look at it directly.

I tried a bunch of different stuff: changing the refresh rate to 23 and 60 hz (60 hz seems to flicker a bit more), changing the resolution, connecting them via VGA etc. nothing seems to work.

So I contacted LG and AMD, asking if they have a solution for the problem. LG referred to the manual saying that I need to have certain horizontal and vertical refresh rates to get rid of the flicker:



Unfortunately I cant figure out how to adjust these fine settings - I only have the options for the general 23,24, 30, 60 and 75hz but not even a separate horizontal and vertical adjustment.

Does anybody has a solution for my problem? Is it the TV? Is it the graphic card? How can I get these refreshment settings, which graphic card supports it?

Thanks for your help guys!!

[TjS2011]

No ideas?

Okay - other question: does anybody connect his Plasma via HDMI to a computer? Do you have any problems with not moving picture?

[handyguy]

LG has free chat tech support on their website. Try it see what they say & report back.

[jman98]

You will have to set the refresh rate on the PC.

[TjS2011]

LG cant find a solution for the problem.
Got a new graphic card today (Nvidia GTX 550 ti), but still have the same problem.

[davexnet]

Perhaps the AVSforum:
http://www.avsforum.com/avs-vb/forumdisplay.php?f=26

[Phlexor]

I have a Nvidia 9500GT connected to a 50" Panasonic Plasma via HDMI with zero problems for a couple of years now.

[TjS2011]

Thats interesting. can you tell wich resolution and refresh rate your using? Did you adjust the timing at all?

I will test another computer later this day, that should give me the (first) final answer

[Phlexor]

Just plugged it all in and worked first time. WinXP SP3 with GeForce Drivers v266.58

1080p @ 60Hz no refresh rate adjustments.

[TjS2011]

haha.... well, thats how it should be!! Its not an old CRT....

[Phlexor]

Oh and don't go beyond GeForce v270 or v275, unless you like windows crashing.

[TjS2011]

you mean the nVidia Control Panel? I had some problems with the original driver - the update fixed it. thx!

[Phlexor]

Just trying to run through ideas, but I don't know if fluro lighting could cause some effect? Do you have all picture processing off on the Plasma TV settings? (like noise reduction and such)

[TjS2011]

Noise reduction and edge enhancer are off - thats basically it. The other settings like Black Level, Color Gamut and Gamma shouldnt have any influence.

[Phlexor]

What about Dynamic Color/Contrast, Film Mode? Might as well play with all of them to see if it has any effect.

[TjS2011]

Everything is off - or on low if it doesn't have a disable mode.

[Phlexor]

And you are running at 60Hz now?

It might just be that you are one of the small percentage of people who just happen to notice Plasma Flicker and I'm afraid there isn't much you can do about it. I don't imagine you'll change to LED/LCD 50" in the near future. I hope it isn't too distracting.

[TjS2011]

Cant imagine it. Its not acceptable right now... I will test it with another computer and go from there...

[Phlexor]

Good luck!

[TjS2011]

Thanks a lot!
Just had an idea: I unplugged all inputs, turned the TV on and opened the Menu/Settings (which is a big white box). It still flickers the same way - so there is no point of trying to find the right computer setting if the TV even flickers without any incoming signal. haha