600E system board - No video out.

[beecee]

I have been given several 600E system boards which all have the same video out problem. Each board has been tested with a known, good sub card & Lcd screen.
Is this a viable, DIY repair job & how do I fix it, or are all the boards scrap?

Also, one of the boards works fine on a battery, but it won't work off the mains or charge the battery. Is this an viable DIY fix, (maybe just de-solder the yellow plug from an old board & fit it to the faulty one) ?

Many thanks to anyone who can help on either or both issues & any suggestions would be much appreciated.

[serverbook]

you may try to switch over subcards etc,if that don't alow power than you could try to resolder or replace the power plug from a known terminal mobo (but with good pin)conversely you can try to use fn+ f7 keys on and off to wake up the lcd screen from external monitor setting
i always set the bios to both lcd and crt always for obvious reasons.
good luck