Dolch MegaPac, No Video

[simba15]

Hi there EEVblog,

So I recently acquired a Dolch MegaPac (Yes huge "Portable" beast) with a nice set of cards and what looks like Pentium-200 cpu.

The frustrating part is that it seems to have no video output (internal LCD or external monitor) even though it sounds like it has completed the POST

Once powered up:
Fans start, power led lit, HDD led lit
Keyboard indicators flash
post beep is audible, then memory tick counter.
Floppy drive seek
HDD led Turns off
then a Dudh-dudh sounds is heard ( I suspect this a secondary error like NO Bootable Drive or Bios Checksum Error.
Numlock, scroll lock or caps lock doesn't function (even with external keyboard)

Strange part is there is no video. Nothing on the internal LCD (not even a backlight flicker) or on the external connector.

If I remove the RAM then power up, the device just gives a constant single beep tone to indicate no memory.

Is it possible that my modern monitor cant display some basic low resolution?
Anyone have any ideas what else I could test for a functional output from the pc ( thinking to probe the VGA connector for sync signals)

Pictures and possible video to come soon.

Thanks.

[simba15]

So in typical vintage electronic fasion I was poking around checking all the voltages. All were OK I tried to measure the sync lines on the vga port and they were driving high. Then all of a sudden the "Du-Du" noise was not present at boot, the sync lines has pulses and the lcd was alive!

No idea why as nothing changed, but typical unplug and plug back in and all was working as it was new.

Here are a few pics. not sure what i should do with it next, I think I have some 30 pin simms around to upgrade to 32mb or so. or do i gut it and make a modern portable system (even just keep the front panel and use a PI)

[m k]

Maybe the power overloaded when more juice was required.
Then some old caps decided to start co-operating.

Did you disconnect all disks before the picture?