A3000 restart after 10 years having video issues

[Zac67]

Video from the VGA port? Take a look at the battery - chances are that it's leaked badly and possibly destroyed Amber circuitry...

[Zac67]

Hmm...

Since the machine does work and isn't crashing I'd rule out chipmem problems for now. Possibly the Denise socket contacts have gone bad (or the chip's damaged), since you've got several machine at hand I'd examine the socket closely, try reseating Denise and/or try to swap it with another machine (a 500/2000/1000 Denise should work as well).

[Zac67]

The A3000 stores some data in its NVRAM, but I wouldn't actually call it vital... The settings safely fall back to sane defaults (SCSI HBA ID 7, fast HDD init, synchronous mode off). Check out http://aminet.net/package/driver/media/SCSIPrefs for details.

[Zac67]

Beware: Ni-MH batteries can leak as well...
Best solution is to move the battery to somewhere it can't do any harm. Or use a coin cell mod.

[Zac67]

No. All RTG cards take the Denise output as an input to their scandoubler. If it is the Denise at fault and not the AMBER then the video will be messed up on RTG card.

Err... Not really correct - not all RTG cards have a scandoubler or use Denise video passthrough. But Miggy just won't boot w/o Denise in place.