42" Toshiba Plasma - Y-Buffer or Bad Screen?


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42" Toshiba Plasma - Y-Buffer or Bad Screen?

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timjamesz06
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May 29, 2014, 10:58 PM

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42" Toshiba Plasma - Y-Buffer or Bad Screen?	Can't Post

I have a 42" TOSHIBA plasma that just keeps on ticking (10 years old now). I have had to replace several boards in the thing (so far, signal board and D-board [logic board]). While the thing is still working about as well as I could ever expect a 10 year old plasma to work, there is a screen artifact that is pretty minor, but it's driving me nuts from a diagnostic standpoint. The TV would be as good as new if I could get this resolved.

I see it most prevalently on areas of the screen that are fairly dark or very have a very uniform dark color. I was able to capture it best when I had the screen displaying a less than totally black solid background (dark grey). The artifacts themselves are tiny horizontal lines of varying length and about a pixel or two tall. The pattern is always consistent. Based on what I know, I tried some obvious fixes like re-seating all the ribbon connections on my screen buffers (both sides). This had no effect. I also had a spare Y-SUS board lying around (thought my original was bad at one point and picked up a replacement that wasn't actually needed). Swapping the Y-SUS board had zero effect. I am running the TV off my PC at the moment (over HDMI), so I messed around with all the various video, color, refresh rate, image enhancement filters, etc, etc on my graphics card and while a lot of those had effects on the TV picture, they had no effect on the artifacts. I tried running off a different source altogether (xbox over component video) and the artifacts remain. I went through all the picture options in the TV menu and none had any effect on the artifacts. I also went into the TV service mode and did the pure display test of RGB and white and every screen in that test looks perfect and solid (no defects or artifacts). I did find it interesting that I'm seeing these things in a definitive pattern (see close up photo) across the entire screen and the pattern isn't split between the top half and bottom half of the screen. I have a feeling that's diagnostically relevant, although I'm not totally sure how.

I am left with the conclusion that it's either bad Y-Buffers (it would have to be both) or the artifacts are actually living inside the ICs that are integral to the screen. I can pick up a pair of Y-Buffers for $30, but I don't even want to throw $30 at a 10 year old TV without some confidence it will resolve the issue. Obviously a screen replacement is out of the question. It's been a point of pride keeping this thing running, so I thought I would at least try and get some other opinions on the matter. I have searched the web and forums and have never seen an artifact quite like this one. See some photos below (one I had the flash on so the problem is less noticeable). And in the photos below, this is sort of the worst case scenario. Under typical viewing circumstances, they aren't nearly that noticeable, although in dark scenes, they can become fairly obtrusive. Thanks in advance for any input.

http://i1076.photobucket.com/...oto3_zpsf1364356.jpg
http://i1076.photobucket.com/...hoto_zps3e4b9a81.jpg
http://i1076.photobucket.com/...oto2_zpsc4d3016c.jpg

(This post was edited by timjamesz06 on May 29, 2014, 11:05 PM)

flyatyou66
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May 30, 2014, 3:54 PM

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Re: [timjamesz06] 42" Toshiba Plasma - Y-Buffer or Bad Screen? [In reply to]	Can't Post

http://www.youtube.com/watch?v=51SZsfH60EY
This is what i did to test my upper and lower on my LG 60 inch Plasma. Mine tested good.Copy and paste. Would be nice to have a model number, then i could give you more information.

(This post was edited by flyatyou66 on May 31, 2014, 12:54 AM)

timjamesz06
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Jun 1, 2014, 3:13 AM

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Re: [flyatyou66] 42" Toshiba Plasma - Y-Buffer or Bad Screen? [In reply to]	Can't Post

My apologies, it's a Toshiba 42HP95. I will try and do some direct testing of the Y-buffers for shorts, although I'd be surprised if I don't find a few with a TV this old (still original buffer boards). It's my understanding that the TV can still function even with some shorts in the buffer, and may even function reasonably well. Additionally, even if buffers check out every way imaginable with a meter, they may still be generating artifacts in the picture. So all that being said, I'll give them the best check I can, but my main hope was that someone has seen an artifact pattern very similar to this or nearly exactly like this and has either determined it to be a buffer problem or has determined it not be a buffer problem.

flyatyou66
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Jun 2, 2014, 2:19 AM

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Re: [timjamesz06] 42" Toshiba Plasma - Y-Buffer or Bad Screen? [In reply to]	Can't Post

Thanks. That helps a lot. I do have a question, do you get any kind of a menu display?
Did you look at the x boards. These are the boards that are located on bottom of tv.These show the vertical lines. IT looks like your problem is vertical with the 100's of pictures i looked at.No i didn't find 1 that looks identical but some really close. Those were lower buffer failure. Maybe check them out.Just clean all the connections going to these 2 boards. I looked at these boards but couldn't find a fuse. Some have a smd fuse some don't.

timjamesz06
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Jun 4, 2014, 9:25 AM

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Re: [flyatyou66] 42" Toshiba Plasma - Y-Buffer or Bad Screen? [In reply to]	Can't Post

I have no problem with the menu, I can get the standard menu and the service menu without any issue. As for the x-boards, if I'm thinking of the same thing you are, I have 4 total, two on top and two on bottom. They are listed in my service manual as 'data driver' boards. Each one has four ribbon connections to the screen (8 on top, 8 on bottom). Each of these boards receives a ribbon cable from the D-board (logic board). I will see if I can pull, clean and reseat all the ribbon connections, but it's difficult since these are behind the sheet metal panel holding the power supplies and signal boards.

As far as the problem being with the vertical or horizontal scan, keeping in mind that I am no expert, I found the following diagram helpful.

http://i1076.photobucket.com/...Line_zpscd882e0f.jpg

With bad 'data driver' boards, or bad components on individual driver boards, or even with bad connections on them, wouldn't I expect to see clearly vertical artifacts (black vertical lines or something of the sort?) With this in mind, it seems based on my non expert opinion that the artifacts I am seeing are horizontal in nature. There is a very definitive pattern to them as well which can best be described as
1)artifacts are comprised of a series of horizontal black lines about 2 pixels tall and separated vertically by about 2 pixels
2)there is a pattern of: WIDE, 2 NARROW, WIDE, 4 NARROW, WIDE, 2 NARROW that is repeating
3)The artifacts span the entire width of the screen, but there are three discrete areas of the screen with the artifacts, leaving two horizontal 'strips' of screen that are completely unaffected. Moreover, while there are three separate areas of artifacts, they have the exact same pattern mentioned above, yet these patterns are offset (the WIDE and NARROW artifacts don't line up on any of the sections affected)

If I knew more about the actual signal processing, I'm sure what I mentioned above would be useful in diagnosing the issue. The only reason I am thinking it's not a vertical scan problem is that the pattern these artifacts are creating isn't consistent through the whole vertical section (or even half the vertical section) of screen.

Here's a photo of a display with a verified Y-buffer going out. While I don't have the red sparkles in the photo which are commonly associated with a failing buffer, the failure seems somewhat similar in nature to the artifacts I am seeing.

http://i1076.photobucket.com/...ct-2_zpscc8459cd.jpg

I will still try and reseat the driver board ribbon cables and see if that has any affect, and when I get a chance I'll pull the buffer boards off as well and test for shorts. Thanks for the input so far.

timjamesz06
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Jun 4, 2014, 11:31 AM

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Re: [timjamesz06] 42" Toshiba Plasma - Y-Buffer or Bad Screen? [In reply to]	Can't Post

I tried reseating all the driver board ribbon cables to the screen, zero effect on the artifacts.

But here's some pretty interesting diagnostics I just did while I was in there. <br> <br>First, I tried a simple test of removing one the driver board ribbon cables to the screen and booting the TV up. It's pretty much what you would expect, with 8 ribbon cables on top, removing one killed 1/8th of the top half of the display (1/16th of the screen total).

http://i1076.photobucket.com/...3939_zps2a2bcd30.jpg

Notice that there are no artifacts in the dead portion of the screen, which is what I would have expected. That portion of the screen is just black. Also notice that the section of the screen that is dead doesn't correlate to the pattern of the artifacts on the screen. But here is where it gets interesting. Next I pulled the top Y-sustain buffer out, not a single ribbon cable, but I unplugged the entire buffer from the y-sustain board.

http://i1076.photobucket.com/...3941_zps3503ec94.jpg

The artifacts remain. Which means, maybe flyatyou66 is correct that it's not a horizontal scan issue. It certainly doesn't look like replacing the y-buffers will have any effect on the issue.

So based on that, just because I completely unplugged one of the ribbons from one of the data driver boards and that deactivated portion of the screen shows no artifacts, doesn't mean that it couldn't be a problem in the board, but for all 4 boards to show the artifacts in a consistent pattern across the entire display seems exceptionally unlikely. Which means I should be considering other boards, or it's the screen itself. I know these artifacts have persisted through two different d-boards (logic board) but I'm thinking perhaps the signal board may be a likely culprit at this point.

(This post was edited by timjamesz06 on Jun 4, 2014, 11:35 AM)

flyatyou66
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Jun 5, 2014, 1:48 AM

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Re: [timjamesz06] 42" Toshiba Plasma - Y-Buffer or Bad Screen? [In reply to]	Can't Post

If you get a menu, it's not the logic board.
Question- do your heatsinks get warm on both the y-sus and z-sus. Why i ask is if they don't get fairly hot that means the y-sus is not working.If there really hot the y-sus is shorted.I don't think this is your problem since you replaced this board.
So this leaves us with only 1 board the main board.The main board can give you all kinds of funny distortions, picture, lines, etc,etc, and still have sound.It's not the screen because of the pattern is that of a screen lacking the right power to do it's job.
I would replace the main board, providing you have heat on y and z board. Have you pressed on the cn connections on the main board.I had a couple plasma with cracked pins fixed screen right up.

timjamesz06
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Jun 5, 2014, 5:32 AM

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Re: [flyatyou66] 42" Toshiba Plasma - Y-Buffer or Bad Screen? [In reply to]	Can't Post

Correct, I get normal and service menus and I know it's not the logic board. I just replaced the logic board because my last one went faulty and my picture would completely drop out intermittently requiring the TV to be rebooted. Bought a used logic board and that fixed that problem. Artifacts were there with the old logic board and the new (new to me but used) logic board. Prior to replacing the logic board, I had replaced the Y-SUS board thinking it was the issue. So I have two perfectly functional Y-SUS boards, and swapping them has no effect on the artifacts. The TV has the original Z-SUS board, but in my early diagnostics, I temperature checked each FET on it and all were nice and warm, but not burning hot, and all were about the same temperature. I could remeasure them for the exact temperature, since I don't have it in my notes, but I wasn't alarmed by the FET or the heatsink temps so I don't think it's a problem with the Z-SUS.

When you say 'the main board' I'm not sure exactly what you're referring to. The only boards I have left (not counting some miscellaneous stuff I'm sure is unrelated) are the signal processing board and the seine board. I think you mean the seine board. Unfortunately, I can't find a replacement seine board cheap enough to justify buying. But additionally, I was under the impression that seine failures, at least on Toshibas were usually accompanied by red LED power light flashes (diagnostic message). I did find a used signal board for $20, almost worth snatching up just as a check, but the only seine board I can find is over $100. When you say CN connections, which connections exactly are your referring to?

timjamesz06
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Jun 5, 2014, 5:58 AM

Post #9 of 20 (5232 views)
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Re: [timjamesz06] 42" Toshiba Plasma - Y-Buffer or Bad Screen? [In reply to]	Can't Post

Wasn't totally sure which connections I should be looking at on the seine board (cn connections?) but I pulled all the data connections (all going to the signal board) and reseated them, also pulled the data connections going from the signal board to the logic board and reseated them. No effect.

To rehash:
- You said at this point its likely the main board, you mean the seine board correct?
- You also said that the pattern is of a screen without the right power to do it's job which is to say you don't think it's a bad screen. Can you explain this any more? I'd love to believe it's not the screen, but I'm not sure I do yet
- Lastly, what 'cn connections' are you talking about on the main board (seine board I'm assuming)?

If it does turn out to be the seine board, I think this TV is destined to become a garage or spare bedroom TV. I'll keep my eye out for a deal on ebay, but I can't justify spending $100 to fix this thing when it work pretty well at the moment. Man would I love to get this last glitch diagnosed and fixed though. Thanks again for the help.

flyatyou66
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Jun 5, 2014, 2:56 PM

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Re: [timjamesz06] 42" Toshiba Plasma - Y-Buffer or Bad Screen? [In reply to]	Can't Post

Sorry. CN is (connections) to the mainboard,seine board or analog board are just diffrent names for same board.The board where the coaxle cord connects to. Just wanted you to check all connections on seine board which you did.Push on those connections to see if it changes picture.
You said:
"Under typical viewing circumstances, they aren't nearly that noticeable, although in dark scenes, they can become fairly obtrusive". Is it possible to get a couple of picctures of your tv when there not that noticeable.
When i said not enough power i ment signal.I'm going to do a serch on your tunner and see what i can find.
I'll wait for pictures.

timjamesz06
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Jun 6, 2014, 3:02 AM

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Re: [flyatyou66] 42" Toshiba Plasma - Y-Buffer or Bad Screen? [In reply to]	Can't Post

Ok, here's a few photos of the problem under some dark scene viewing.

Dark scene in 'Hunger Games 2'
http://i1076.photobucket.com/...age_zps1dbd85db.jpeg

Close ups of same scene showing artifacts
http://i1076.photobucket.com/...e_2_zpsd1e33abe.jpeg
http://i1076.photobucket.com/...e_1_zps72891003.jpeg

Not a particularly dark scene, but one that shows issue in 'Escape Plan'
http://i1076.photobucket.com/...e_3_zpsc288413d.jpeg

Another not particularly dark scene in a cartoon where a solid color shows artifacts heavily
http://i1076.photobucket.com/...e_4_zps797c9a7c.jpeg

I actually just pulled up paint and tried to modify a solid color to see what would show the artifacts heavily and what wouldn't. Pure solid colors (RGB) don't show the artifacts. Even darkening the colors (ie shifting toward black) won't show the artifacts. You can sort of make them out as you shift a solid color to black, but only ever so slightly. Where they really begin to show up is when you take a lighter color and shift it toward black. When it's a solid light color you don't see anything, but as you shift to toward black (remove brightness or however you want to think about it) you begin to see the artifacts. The worst case (as in my original photos of the problem) is when you shift white slowly to black. Once you hit medium to dark gray the artifacts really become apparent. Once you hit full black (since the artifacts themselves are black pixels) you can no longer see the issue. Based on this it seems that these 'problem pixels', which again never move, are premature to jump to black. So when the commanded color for the area of the screen is something near dark (near black) and a mix of RGB (ie not solid R,G, or B) these areas jump straight to black prematurely leaving black artifacts in the screen. At least that is the best way I can verbally describe it.

flyatyou66
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Jun 6, 2014, 1:28 PM

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Re: [timjamesz06] 42" Toshiba Plasma - Y-Buffer or Bad Screen? [In reply to]	Can't Post

Good pictures. How old is your logic board and when you replaced it was it brand new? Those pictures all point to the logic board.

Try this, it might help. Performing a Power Cycle Step 1
Locate the power supply for the TV and unplug it from the electrical outlet. Step 2
Press and hold the "Power" button on the TV for 60 seconds. Step 3
Plug the power supply of the TV back into the wall and press the "Power" button to restart the TV. Perform a Factory Reset Step 1
Turn the television on. Step 2
Press and hold the reset button on the remote control. If your remote control doesn't have a reset button, press and hold the up arrow. Step 3
Press the "Power" button on the front panel of the television while holding the reset or up arrow button on the remote. Step 4
Release the reset or up arrow button on the remote and follow the setup instructions on the screen

(This post was edited by flyatyou66 on Jun 6, 2014, 1:44 PM)

timjamesz06
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Jun 6, 2014, 2:02 PM

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Re: [flyatyou66] 42" Toshiba Plasma - Y-Buffer or Bad Screen? [In reply to]	Can't Post

I'll give all that a shot this afternoon. I can only assume the logic board that I replaced the faulty one with was used but tested as functional. For the price I paid for it, no way it was brand new. The failure behind replacing the logic board was that after some hours of use (or sometimes days) the picture would flicker and then go completely black and stay that was until the computer was unplugged for 10 seconds and rebooted. Replacing the logic board has completely fixed that issue, but the artifacts remain with the replaced board.

I will post back after trying the resets you mentioned.

timjamesz06
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Jun 7, 2014, 1:50 AM

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Re: [timjamesz06] 42" Toshiba Plasma - Y-Buffer or Bad Screen? [In reply to]	Can't Post

Tried the power cycle and the factory reset (process described in my manual is different than what you described and the method you gave for a factory reset didn't seem to work, but I still believe what I did was a full blown factory reset). Neither had any effect on the issue.

What I'm thinking at the moment is I will go ahead and swap back in the old logic board just to make absolutely sure that the artifacts are still there and are the same. If that is truly the case, I don't see how it could be the logic board.

As I mentioned previously, I did change out the signal board a long time ago (like when I swapped the Y-buffer this was an attempt to fix the loss of picture problem, which turned out to be caused by the logic board so there was probably never an issue with the signal board). Unfortunately, that was a quite a while ago and I can't find the original signal board anywhere. What I had never noticed is the replacement signal board is listed as coming from a 42HPX95 (mine is a 42HP95). The board itself has the same part number, but when I go into my system information on the TV menu, it actually lists the TV as a model: 42HPX95. So there is information/firmware (on an EEPROM I'm assuming) on the signal board that is not exactly for this TV. All that being said, I have to assume the firmware/software is compatible or the TV wouldn't function as well as it does, but it does make me wonder about updating firmware on the boards (signal and/or seine) to see if that has any effect. Do you have any experience with firmware updates?

I did find a signal board and seine board combo (used) on ebay specifically from a 42HP95. If I can talk the seller down in price a little, I may try to grab both. Before I try that though, I will swap out the replacement logic board with the original and observe the behavior of the artifacts to rule it out. Furthermore, I'd like to try a firmware upgrade if that is at all possible.

Note: I haven't mentioned it before, but I have tuned all my system voltages to the published ranges in the service manual, and I double checked them again yesterday. They are all still in the appropriate ranges.

(This post was edited by timjamesz06 on Jun 7, 2014, 1:51 AM)

flyatyou66
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Jun 7, 2014, 3:51 PM

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Re: [timjamesz06] 42" Toshiba Plasma - Y-Buffer or Bad Screen? [In reply to]	Can't Post

No, don't know nothing about firmware updates at this time.
Take another good look at your LVDS cable.Sometimes this can cause interference to the screen. Other than that I have no more ideas.You just got to live with it.

timjamesz06
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Jun 9, 2014, 5:58 PM

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Re: [flyatyou66] 42" Toshiba Plasma - Y-Buffer or Bad Screen? [In reply to]	Can't Post

I really appreciate all the help you've provided so far flyatyou66. Maybe you can clear up one more thing for me. Mistake me if I'm incorrect, but the seine board doesn't process the digital signal from the HDMI at all. Here's the circuit block diagram from my service manual.
http://i1076.photobucket.com/...tled_zps385d97fc.jpg
From what I can tell, the seine board only processes information from the digital tuner. So if I'm getting these artifacts on HDMI and component video, wouldn't that mean that it can't be a problem with the seine board? I'd like to see what you think on the issue, because if I'm right on that and considering everything else I've determined along the way, wouldn't it make sense at this juncture that it's either the signal board or the screen itself? I found a signal board for $20 and I'm willing to take a stab at swapping it. Thanks.

flyatyou66
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Jun 10, 2014, 7:59 PM

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Re: [timjamesz06] 42" Toshiba Plasma - Y-Buffer or Bad Screen? [In reply to]	Can't Post

http://www.amazon.com/...PD2222/dp/B00J4XK0FY

TOSHIBA PD2266 SEINE BOARD REPAIR KIT 42HP95 42HPX95
After more research i found this artical:
The menu is the last thing generated on the digital board, therefore if the problem is behind the menu as it is in your case then the problem is on the digital board. This board will require replacement to fix the set, and what makes this worse is that on your model if you replace the digital board you must also replace the analog board at the same time or the new digital board will not work.
You have alreaady replaced the seine board ( PD2222D1--OR U102) now you have to replace signal board (PD2222B1 OR U101) it's in schematic.
This is why you are getting distortion behind menu display.
When you replace 1 you haaave to replace the other.

timjamesz06
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Jun 10, 2014, 8:54 PM

Post #18 of 20 (5133 views)
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Re: [flyatyou66] 42" Toshiba Plasma - Y-Buffer or Bad Screen? [In reply to]	Can't Post

That's kind of funny, that part you linked to is sold by payless components, where I always buy my parts from anyway.

But I'm a little confused by your following comment. You're saying digital board, as in the digital signal board, correct? Not to be confused with the d-board (which according to my service manual is the name for the logic board, ie the post LVDS logic board that sends the signals to the Y-SUS and Z-SUS and data drivers).

To be clear, I have replaced the digital signal board in the past (it ended up not being necessary but it was first attempt to fix an unrelated problem) without replacing any other boards and the set worked fine (artifacts were present, but otherwise fine). And I have never replaced the seine board on the tv.

But what you're saying, if I am interpreting this correctly, is that if you replace the digital signal board, you must also replace the seine board (the analog signal board) or the digital board 'will not work'. This is certainly not the case based on what I have done in the past. The digital signal board definitely 'works' unless you consider the presence of these artifacts 'not working'. Moreover, I don't understand why replacing both boards together would be necessary, at least not for digital signals. The digital signals never back up into the seine board according to the block diagram. Heck, I can (and have) unplug power to the seine board altogether and the picture stays exactly the same.

Regarding the menu, yes the menu comes up and looks fine, but that is not to say that the problem isn't still present on the menu objects themselves (since the artifacts only show up on very particular circumstances, they could easily still be present on the menu items and just not visible because of the colors/brightness of the menu items).

All that being said, unless you think it will be a complete waste, I'm still convinced that the only thing to try at this point is to replace the digital signal board ($25), and if that doesn't fix it, then it's most likely the screen itself or something else that I'm not going to figure out without replacing and swapping lots of boards. Worse case I can resell the signal board for a slight loss. The deal I was trying to get for both the seine and the digital signal board together fell through (guy wanted $55 bucks for both, which is a good deal, but just isn't justifiable to me especially since I don't think replacing the seine board is going to help at all). And regardless what someone may say about replacing both at the same time, I'm going off the signal block diagram, and I don't see how the seine board affects digital signals entering and leaving the digital signal board directly unless someone can elaborate on this and explain in detail why they must both be replaced. To me, that just sounds like someone's way of getting you to buy two replacement boards when you may not need both.

Hope I'm not coming off as an a**hole, and I truly appreciate your research and help on this. But the service manual doesn't state that both boards have to be replaced at the same time, the block diagram doesn't show anything to support it, so I need something more to go on before I believe it. If that is the case, why would toshiba ever have sold the boards separately?

flyatyou66
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Jun 11, 2014, 1:06 AM

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Re: [timjamesz06] 42" Toshiba Plasma - Y-Buffer or Bad Screen? [In reply to]	Can't Post

could you send me a picture of main board

timjamesz06
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Jun 14, 2014, 10:23 PM

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Re: [flyatyou66] 42" Toshiba Plasma - Y-Buffer or Bad Screen? [In reply to]	Can't Post

Ok, this is a little embarrassing, but I actually figured out the underlying cause of the problem.

I was about to order a new digital signal board, but given all the questions raised about which signals are being processed by which boards I wanted to be as sure as possible ordering a replacement signal board made sense.

I swapped out the logic board (d-board, post LVDS board) with my old one, the issue remained. Then I tried to tune into a digital HD broadcast signal but didn't' have much luck since I don't own any kind of UHF/VHF antenna. So I put my Xbox 360 on the TV via HDMI and tried to find some content that would show the artifacts (I had already done this, but it's difficult to find content on the Xbox or a DVD player that shows the artifacts since you don't have the same control as playing a file off the PC). I was having a hard time finding and pausing content on the Xbox that would clearly and undeniably show the artifacts (I thought I saw them, but it was hard to tell for sure). So I decided to try something different and use the DVI output from my PC graphics card into the VGA input on the television (previously using HDMI). The issue remained with this setup. Then using the same video files/content, I tried using HDMI off a laptop. Suddenly, the artifacts were gone. I know I had previously stated that the artifacts were present and independent of the video signal source, but my testing on this was not nearly as comprehensive as it ought to have been.

This is what I figured out after much tinkering, and again with much personal embarrassment. Any video output off my PC (nvidia geforce) graphics card would result in artifacts on the Toshiba plasma (not on my 24" ASUS montior). Same files sources output from my laptop (ATI Radeon graphics card) showed up fine without artifacts. This is an old PC I built (4-5 years ago) so I honestly thought my graphics card had gone south. And while I had already screwed with all the settings on the graphics card, turns out I had missed something.

Underneath my Nvidia control panel, there are two sections which allow either the Nvidia software or another software (ie Windows) control color settings. I had tweaked all the color setting via the Nvidia software and on the TV itself with no effect on the artifacts. What I had failed to notice was that I was specifically tweaking video playback color options. Underneath 'desktop display color settings', I had not even given the Nvidia software permission to control the color settings. Simply by clicking 'Use Nvidia settings' the artifacts disappear. I have since tried to isolate exactly which color setting in question is responsible for generating the problem, but so far I haven't been able to find it. Simply put, allowing windows to control the display color options generates the artifacts and going back to Nvidia settings gets rid of them. Everything on the surface setting wise (contrast, brightness, gamma, hue, color depth, 16bit or 32bit, etc) looks the same between windows and the nvidia control panel. But obviously allows the windows settings to control the nvidia card is somehow causing these artifacts.

My apologies for overlooking this, but hopefully this thread will help someone else diagnose their television's issues. I know I learned a lot from flyatyou66's input and my own research. I appreciate the help with this issue and my apologies for not doing as complete of an initial diagnosis as I should have done.

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