Old TFT Panel distortion - Looking for advice

[rfdes]

Hi -
I'm hoping someone knowledgable with TFT flat panels could provide me with some troubleshooting tips.  I am in the process of replacing a defective LCD panel from a piece of test equipment EOL 20+yrs.  I've replaced the panel in this same unit in the past using a laptop screen from a scrapped unit.  The display was an old Hitachi panel and it gave me no problems, it worked well. 

Well that display also went belly up so now I'm trying to shoe horn an obsolete Sharp LQ10DS05 800x600 SVGA TFT display into the unit and its giving me problems.  The display was unused NOS and dirt cheap (why I bought it).  Unfortunately the datasheet is nowhere to be found, so I just pushed forward as the electrical interface pin out is the same from other Sharp displays in the '95 time frame.

The issue is the display is tearing while displaying graphics images (see pictures).  However, while displaying DOS text type video it seems OK.  I know I have some vertical timing tweaks that need attention, but I am wondering if the tearing is related to timing or if it is due to defective panel hardware. I could use some direction as to how to verify whether the panel is electrically defective or not.  Unfortunately, I have no other source of video other than the piece of test equipment that I am restoring.  I'm leaning on the display being defective.

Any advice would be appreciated. 

[eTobey]

You should try another panel. What happen with the last one? Maybe the videocard is destroying the panels?

[rfdes]

The old display failed due to physical damage.  The screen became damaged due to the so-called 'vinegar syndrome', I believe.  Electrically it worked fine but the optics failed.  I've ordered another cheap display from the same vendor.  Maybe a mistake but I don't want to point fingers until I can isolate the failure.

[inse]

Windows driver switching the refresh rate?

[squadchannel]

some NEC displays are listed on yahoo auctions japan.
https://auctions.yahoo.co.jp/jp/auction/w1176499034
https://auctions.yahoo.co.jp/jp/auction/s1182561518
cheap!

shipping cost, hmmm.

Windows driver switching the refresh rate?

VBIOS has several modes. It definitely switches to a different mode for Windows and DOS.
The second method is modifying the VBIOS, but what graphics chip is used?

[rfdes]

The video controller is a Cirrus Logic GD-7543 and I've already been working on playing with the timing of the display.  However, nothing I do seems to resolve the 'tearing' shown in the pics.  I'm believing that the panel is damaged electrically.  I was hoping someone may have experienced a similar situation and could provide their opinion.   I should mention that I have scoped the timing signals and they look clean and within spec.  I wish I had a detailed datasheet as I am trying to make educated guesses.  I found Sharp datasheets for other panels from the same era as the one I own and have been using it as a guide.

So, the question:
Timing?
Electrical failure?
Signal Integrity issue?

[Bud]

Not a graphical panel in the first place?

[amyk]

Not a graphical panel in the first place?

No such thing, they are all "graphical". The tearing suggests it may be running at too high of a pixel clock for the panel, so turn down the refresh rate if you can. Otherwise check for signal integrity issues.

Since this system appears to be more or less a standard PC, is the display controller integrated into the mobo or on an add-in card? If the latter, or the former and there are ISA/PCI slots, I would try putting in a standard GPU as with one of those you will have a wide range of monitors to choose from.

[Rafiki]

I also think you did not set refresh rate to the correct 60Hz in windoze settings. Most probably 50Hz will work too.