HappyDonut wrote on 2025-01-04, 21:32:

So, technically a Finisar GT, but as I understand it's a rebadge of the Dolch Pac 65 (P2/400, 256MB RAM, WinNT 4.0, 120GB HDD, 1 […]
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So, technically a Finisar GT, but as I understand it's a rebadge of the Dolch Pac 65 (P2/400, 256MB RAM, WinNT 4.0, 120GB HDD, 120MB LS120, some random thin cd-rw)
I bought it online from a seller stating the screen was "defective"
Get it in, fires right up, no issues. Super happy. Shut it down, move it to another place, await a serial mouse from eBay.

Mouse comes in, fire system up...white screen. More research online. Maybe bad video cable?

Disassemble case, wiggle cable. Video comes back, through repeated power on and power off. Super happy about that, it works, hooray!
Reassemble. White screen comes back, and I was careful about cable placement.
Take it apart again, cable still looks good, but white screen (or whiteish with vertical lines) back, and seems to stay regardless of what I do.

So...bad cable for certain? Or something else? Can the cables be had any more? I can always eliminate the cable as source of the issue if I can get a replacement. The company that made the cables still exists, but I've not yet reached out to them.
I'm open to suggestions...

Hey welcome to the forum 😀 Very cool that it's got an LS120 in it too

What do the vertical lines look like? Also does the VGA output work? Looks like you have to switch a jumper to go between LCD and CRT modes.

The white screen means the backlight is powered up but the display section isn't running, but hopefully the rest of the machine is running fine. I don't know if you've seen curiousmarc's videos and page about the Dolch Pac 65 but it's quite comprehensive: https://www.curiousmarc.com/computing/dolchpa … -65-luggable-pc

The LCD screen uses one of those DF9-41 connectors on the LCD. The LCD is pretty standard and it's not from an era where bad caps would be breaking the display, can't see any electrolytics on the LCD picture on marc's page.

There are multiple levels of connector it looks like and if your board is set up the same as curiousmarc's LCD panel, there's a sub-board on the main single board computer that converts the parallel LCD signals from the VGA chip into LVDS signal.
That then goes through a basic ribbon cable? to the LCD connector of the LCD, which looks like there's another sub-board that screws onto the LCD metal housing that converts *back* to parallel signal for the LCD - I say this because DF9-41 type connectors are most often parallel TTL LCD signals, while LVDS would use a much smaller 20-pin / 30-pin type connector.
If the LCD cable is that basic ribbon cable, it's unlikely that's at fault since ribbon cables are quite robust. LVDS signal is a high speed serial encapsulation of parallel lcd signals that's less prone to interference and worked much better as LCD resolutions went above 800x600.

You could try unscrewing the board that connects the LCD panel to the LCD cable and re-seat that connector a few times with some contact cleaner - I've found that those often get oxidised after enough years and re-seating them a few times usually gets them back to normal, my most recent fix had vertical coloured bars displayed on the screen til I cleaned the contacts on its display cable.

Hope that helps, some pictures of the situation might help also if it's a more involved issue 😀

Thank you for the reply!
The VGA output works automagically, but I get video corruption out to a known good monitor. The screen on the Finisar GT is 1024x768, 65k colours (it'll do 'true colour' at a reduced resolution of 800x600) but when the built-in display is white, the VGA output looks like 16 colours, and any attempt to correct this in the Win NT4.0 hard locks the OS.
But when the system first booted up and was behaving, then output to the VGA monitor was fine. This is why I thought ribbon cable.
And yes, the mainboard has a sub-board that is the GPU (or whatever it functions as) where the ribbon cable, which is a smaller 26pin ribbon cable connector, goes. It's glued on on both ends, on the sub-board connector and on the built-in monitor end. I've not attempted to remove that, but the sub-board is screwed in, and I will try removing that and cleaning the connectors.

I will get some images of the white screen when I can (ASAP!) as well as the internals of the system.
I did see Curious Marc's videos while searching for info, sadly, I'm not an elec engineer and all the schematics just simply go over my head.
As far as I can tell, everything else is in fully functional order, keyboard, serial ports, HDD, CD-ROM, OS doesn't act corrupt, etc. Just the video.

Attempting to add images to the post, apologies for the poor quality, the system is only partially disassembled.

The main board has the default PS/2 and VGA out, and the VGA out port has a VGA extension cable (along with standard NIC) which is currently not installed (I suspected the cable might have been bad or causing a short, so currently it's removed) so I can't get you images from my VGA monitor, but I'll get it to you ASAP.

The attached image is the other end of the video ribbon cable connection where it connects to the LCD. Again, apologies for the quality, things are tight in there. The cable is full of glue and it looks like it's either come undone from where it's supposed to have been, or someone before me tried to glue it down (and made a royal mess if you ask me)

PS, the white screen images are during the POST boot up phase, the HDD has been disconnected so the system never gets to the OS.