VOGONS


First post, by raindog

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Around 2000/2001, the plasma screen of my t5200 stopped working but I could still use the computer with a separate VGA monitor, a while after the VGA output also stopped working. Every few years I try to investigate why it doesnt work.

Today I tried again - to my delight the orange screen showed the memory self check, then displayed an error about config(?), I got into BIOS settings with F10, then exited the settings, the screen then showed something about "insert system disk and press any key". Even with a 3.5" system disk in A the same message appeared, the FDD disk light came on so I could see it trying to access the floppy - tried with switch in B and PRT settings. Then the screen went blank (both plasma and VGA) and with any restarts of the computer after that the screen was still blank.

I recall last time I tried to investigate the t5200 problems (a few years ago) a similar thing happened - the screen worked for a few minutes then went blank and nothing I did brought the display back. Do I have to wait a another few years before I try again 😀 ?

Today I found this forum which seems active on t5200 matters. After reading through the posts, I disconnected and took out the lithium battery (I as think the initial config error would have been about the date) but still the screen displays nothing. I think it's probably still trying to show me the "insert system disk and press any key" message because when I put in a 3.5" disk in and press a key the FDD light goes on.

So
- screen not working (plasma and external VGA)
- not booting from HDD nor FDD
Could the same issue causing both these things ? Any suggestions for getting the screen working so that I can at least diagnose the boot issues ...?

Thanks
Robert

Reply 1 of 2, by IanB

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Here are a few things that can stop the plasma display from working:
There is a switch that blanks the display when the lid is closed and that might be faulty. (It's by the right hand cluster of LEDs when you remove the case top). Unless depressed, it will also stop the plasma from working when the case top is removed.
The high voltage converter might have failed due to bad capacitors. It's in the plastic 'lump' that is hanging under the screen when you disconnect the screen from the rest of the case. Warning this may contain dangerously high voltages in the capacitors even when switched off so should only be looked at if you know what you are doing.
The controller board mounted behind the screen has failed. This happened to one of my T5200s but that resulted in a bright orange line on the bottom of the screen although it would sometimes work normally. I fixed it by swapping the board with one from a T5200 with a smashed screen that someone was breaking for parts.

However, the above would only stop the screen from working and you mention that the VGA has now failed as well so the only other thing I can suggest is to remove the back panel to access the ISA slots which will also give access to the VGA controller board. Pull the VGA and IO boards out (they are screwed together) and spray the connectors with contact cleaner and reseat them and see if that makes any difference. You might also try removing the bolts that connect the two boards together and reseating them as well before plugging the assembly back in.
It's probably a good idea to fit a new CMOS battery as well as sometimes no battery can mess up the plasma display.

Reply 2 of 2, by Honzis

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Hi,
IanB is absolutely right...
These ones are so old, so capacitors inside are really aged in most cases. I've two T5200's, one with plasma, one with color LCD. Both had same problem. If you detach LCD and main unit, behind the LCD remains a "box". In thos box inverter for display is hidden. Both of mine had failed capacitors in this box. Plasma one faded out after several seconds, LCD turned to white screen and next the backlight dimmed resulting in totally dead screen. Replaced several caps ( if I remember, 4 pieces) and it is working again.